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Cu/TEMPO catalyst systems show reduced reactivity in aerobic oxidation of aliphatic and secondary alcohols. A catalyst system consisting of (MeObpy)CuOTf and ABNO mediates aerobic oxidation of primary, secondary allylic, benzylic, and aliphatic alcohols with nearly equal efficiency. The catalyst exhibits broad functional group compatibility, and most reactions are complete within 1 h at room temperature using ambient air as oxidant.
J. E. Steves, S. S. Stahl, J. Am. Chem. Soc., 2013, 135, 15742-15745.

A (bpy)CuI/TEMPO catalyst system enables an efficient and selective aerobic oxidation of a broad range of primary alcohols, including allylic, benzylic, and aliphatic derivatives, to the corresponding aldehydes using readily available reagents, at room temperature with ambient air as the oxidant. The catalyst system is compatible with a wide range of functional groups and shows a high selectivity for 1° alcohols.
J. M. Hoover, S. S. Stahl, J. Am. Chem. Soc., 2011, 133, 16901-16910.

Imidazolium salts bearing TEMPO groups generate in situ Cu-NHC-TEMPO complexes with commercially available copper powder. These easily available Cu-NHC-TEMPO complexes are quite efficient catalysts for selective, aerobic oxidation of primary alcohols into aldehydes in excellent yields.
X. Liu, Q. Xia, Y. Zhang, C. Chen, W. Chen, J. Org. Chem., 2013, 78, 8531-8536.

The combination of TEMPO and CAN can be used for the aerobic oxidation of benzylic and allylic alcohols into their corresponding carbonyl compounds. However, steric hindrance has been observed to impede the reaction with some substituted allylic systems. The present method is superior to others currently available due to its relatively short reaction times and excellent yields.
S. S. Kim, H. C. Jung, Synthesis, 2003, 2135-2137.

A convenient method enables the preparation of a silica gel supported  TEMPO catalyst. The catalyst prepared from [4-hydroxy-TEMPO + NaCl]/SiO2 was used for an aerobic oxidation of alcohols to carbonyls under mild reaction conditions in the presence of Fe(NO3)3 • 9 H2O. Alcohols were converted to the corresponding carbonyls in good to excellent yields. After a simple filtration, the catalyst can be reused at least six times.
N. Tamura, T. Aoyama, T. Takido, M. Kodomari, Synlett, 2012, 23, 1397-1407.

TEMPO-derived reagents tagged with multiple perfluoroalkyl chains and triazole moieties promote the oxidation of alcohols to aldehydes in organic solvent/water mixtures with reaction rates comparable to homogeneous TEMPO reagents, but can be easily recovered by liquid/emulsion filtration.
A. Gheorghe, T. Chinnusamy, E. Cuevas-Yañez, P. Hilgers, O. Reiser, Org. Lett., 2008, 10, 4171-4174.

The use of low loadings of a silver NHC catalysts enables a mild, selective oxidation of alcohols to aldehydes or carboxylic acids in the presence of BnMe3NOH or KOH under dry air in excellent yield. The catalytic system can also be used for a one-pot synthesis of imines in excellent yield.
L. Han, P. Xing, B. Jiang, Org. Lett., 2014, 16, 3428-3431.

A robust and effective Pd catalyst for the aerobic oxidation of various alcohols has been discovered. Using a slightly higher concentration of acetic acid as additive and extending the reaction times, the oxidation can be carried out under ambient atmosphere of air.
D. R. Jensen, M. J. Schultz, J. A. Mueller, M. S. Sigman, Angew. Chem. Int. Ed., 2003, 42, 3810-3813.

Pd/C in aqueous alcohol with molecular oxygen, sodium borohydride, and potassium carbonate efficiently oxidized benzylic and allylic alcohols. Sodium borohydride allows a remarkable reactivation of active sites of the Pd surface.
G. An, M. Lim, K.-S. Chun, H. Rhee, Synlett, 2007, 95-98.

A new, highly recoverable palladium-based catalyst for the aerobic oxidation of alcohols combines an organic ligand and mesoporous channels that led to enhanced activity, prevention of agglomeration and the generation of a durable catalyst.
B. Karimi, S. Abedi, J. H. Clark, V. Budarin, Angew. Chem. Int. Ed., 2006, 45, 4776-4779.

Copper N-heterocyclic carbene complexes serve as catalysts for both aerobic oxidation of alcohols to aldehydes and reduction of imines to amines. A one-pot tandem synthetic strategy affords useful secondary amines from benzylic alcohols and anilines via an oxidation-reduction strategy.
L.-W. Zhan, L. Han, P. Xing, B. Jiang, Org. Lett., 2015, 17, 5990-5993.

N-functionalized amino acids serve as powerful N,O-bidentate ligands in an aerobic copper/TEMPO-catalyzed system for the oxidation of benzylic alcohols in water. Under optimized reaction conditions, a broad range of primary and secondary benzylic alcohols have been efficiently converted into carbonyl compounds in very good yields.
G. Zhang, J. Lei, X. Han, Y. Luan, C. Ding, S. Shan, Synlett, 2015, 26, 779-784.

G. Zhang, J. Lei, X. Han, Y. Luan, C. Ding, S. Shan, Synlett, 2015, 26, 779-784.

Various imidazolium salts bearing hydrophilic groups afford water-soluble NHC copper complexes. These copper complexes catalyze a selective oxidation of benzyl alcohols to the corresponding aldehydes in water at room temperature without the need for a base.
C. Chen, B. Liu, W. Chen, Synthesis, 2013, 45, 3387-3391.

Optimized selective aerobic oxidations in ionic liquids convert various activated primary alcohols into their corresponding acids or aldehydes in good to excellent yields. The newly developed catalytic systems could also be recycled and reused for three runs without any significant loss of catalytic activity.
N. Jiang, A. J. Ragauskas, J. Org. Chem., 2007, 72, 7030-7033.

The reaction of KBrO3 and NH2OH • HCl in situ generates NOx and Br anion, which allows in the presence of 2,2,6,6-tetramethylpiperidine-N-oxide (TEMPO) an activation of dioxygen to oxidize various benzylic alcohols quantitatively to their corresponding carbonyl compounds under mild conditions.
G. Yang, W. Wang, W. Zhu, C. An, X. Gao, M. Song, Synlett, 2010, 437-440.

A copper-catalyzed aerobic C-C cleavage of single bonds enables a transformation of epoxides into ketones.
L. Gu, C. Jin, H. Zhang, L. Zhang, J. Org. Chem., 2014, 79, 8453-8456.

A mild and operationally simple protocol for the selective aerobic oxidation of aromatic olefins to carbonyl compounds is catalyzed by a Fe(III) species bearing a pyridine bisimidazoline ligand at 1 atm of O2. The method cleaves α- and β-substituted styrenes to afford benzaldehydes and aromatic ketones in high yields with excellent chemoselectivity and very good functional group tolerance.
A. Gonzalez-de-Castro, J. Xiao, J. Am. Chem. Soc., 2015, 137, 8206-8218.

In a 2,2-azobis(isobutyronitrile)-catalyzed oxidative cleavage of gem-disubstituted alkenes with molecular oxygen as the oxidant, carbonyl compounds were obtained as the desired products in high yield under mild conditions.
G.-Z. Wang, X.-L. Li, J.-J. Dai, H.-J. Xu, J. Org. Chem., 2014, 79, 7220-7225.

A cobalt-catalyzed peroxidation of silyl enol ethers with molecular oxygen and triethylsilane provides silyl monoperoxyketals in good yield. These compounds serve as precursors to peroxycarbenium ions, which undergo annulations to provide 1,2-dioxolanes.
B. Hurlocker, M. R. Miner, K. A. Woerpel, Org. Lett., 2014, 16, 4280-4283.

Aryl radicals generated in situ from arene diazonium fluoroborates promoted by ascorbic acid enable a convenient and general oxidative arylation of vinyl arenes in air at room temperature in the absence of any additive and visible light irradiation. Various 2-aryl acetophenones have been obtained in good yields.
B. Majhi, D. Kundu, B. C. Ranu, J. Org. Chem., 2015, 80, 7739-7745.

A metal-free and green catalytic system enables an oxyfluorination of olefins for the synthesis of α-fluoroketones which is an important building block for organic synthesis. Moreover, this reaction system exhibits great functional group tolerance.
Q. Yang, L.-L. Mao, B. Yang, S.-D. Yang, Org. Lett., 2014, 16, 3460-3463.

The use of low loadings of a silver NHC catalysts enables a mild, selective oxidation of alcohols to aldehydes or carboxylic acids in the presence of BnMe3NOH or KOH under dry air in excellent yield. The catalytic system can also be used for a one-pot synthesis of imines in excellent yield.
L. Han, P. Xing, B. Jiang, Org. Lett., 2014, 16, 3428-3431.

Pd/C along with NaBH4 in aqueous ethanol or methanol and either K2CO3 or KOH as base at room temperature under molecular oxygen or air is capable of oxidizing alcohols to its desired carbonyl or carboxyl counterpart. Room temperature reaction in aqueous system and recyclability of the catalyst make the process safe and cheaper.
G. An, H. Ahn, K. A. De Castro, H. Rhee, Synthesis, 2010, 477-485.

N. Jiang, A. J. Ragauskas, J. Org. Chem., 2007, 72, 7030-7033.

The use of a NaOtBu-O2 resulted in an efficient oxidative cleavage of vic-1,2-diols to form carboxylic acids in high yields. The present protocol is a green alternative to conventional transition metal based methods. Large-scale production with nonchromatographic purification is also possible.
S. M. Kim, D. W. Kim, J. W. Yang, Org. Lett., 2014, 16, 2876-2879.

A copper-catalyzed aerobic oxidative decarboxylation of phenylacetic acids and α-hydroxyphenylacetic acids enables the synthesis aromatic carbonyl compounds via decarboxylation, dioxygen activation, and C-H bond oxidation steps in a one-pot protocol with molecular oxygen as the sole terminal oxidant.
Q. Feng, Q. Song, J. Org. Chem., 2014, 79, 1867-1871.

The visible-light mediated oxidative C-C bond cleavage of aldehydes has been achieved in good yields at ambient temperature and open to air using Ru(bpy)3Cl2 as the photoredox catalyst.
H. Sun, C. Yang, F. Gao, Z. Li, W. Xia, Org. Lett., 2013, 15, 624-627.

A facile synthesis of aryl carboxylic acids from aryl ketones by aerobic photooxidation using the inexpensive and easily handled CBr4 as catalyst is applicable to inert compounds under usual photo-irradiation conditions, and appears very attractive for the expansion of the Norrish Type I reaction.
S.-i. Hirashima, T. Nobuta, N. Tada, A. Itoh, Synlett, 2009, 2017-2019.

A facile and mild photooxidation of alcohols gives carboxylic acids and ketones using easily handled 2-chloroanthraquinone as an organocatalyst under visible light irradiation in an air atmosphere.
Y. Shimada, K. Hattori, N. Tada, T. Miura, A. Itoh, Synthesis, 2013, 45, 2684-2688.

A readily accessible catalyst system consisting of Pd/charcoal in combination with bismuth(III) nitrate and tellurium metal enables an efficient aerobic oxidative methyl esterification of primary alcohols, exhibits a broad substrate scope, and is effective with both activated and unactivated alcohols bearing diverse functional groups. The Bi and Te additives significantly increase the reaction rate, selectivity, and overall product yields.
A. B. Powell, S. S. Stahl, Org. Lett., 2013, 15, 5072-5075.

In a Cu-catalyzed aerobic oxidative esterification of simple ketones via C-C bond cleavage, various common ketones, even inactive aryl long-chain alkyl ketones, are selectively converted into esters. The reaction tolerates a wide range of alcohols, including primary and secondary alcohols, chiral alcohols with retention of the configuration and electron-deficient phenols.
X. Huang, X. Li, M. Zou, S. Song, C. Tang, Y. Yuan, N. Jiao, J. Am. Chem. Soc., 2014, 136, 14858-14865.

Copper-catalyzed aerobic oxidative esterification of acetophenones with alcohols using molecular oxygen gives a broad range of α-ketoesters in good yields. Mechanism studies evealed that the carbonyl oxygen in the ester mainly originated from dioxygen.
X. Xu, W. Ding, Y. Lin, Q. Song, Org. Lett., 2015, 17, 516-519.

A copper-catalyzed one-pot strategy for the synthesis of α-ketoamides from 1-arylethanols is highly efficient and delivers product in very good yields via alcohol oxidation, sp3 C-H oxidation, and oxidative amidation.
N. Sharma, S. S. Kotha, N. Lahiri, G. Sekar, Synthesis, 2015, 47, 726-736.

An eco-friendly and mild aerobic oxidation of allylic alcohols using Fe(NO3)3·9H2O/TEMPO/NaCl as catalysts under atmospheric pressure of oxygen at room temperature provides a convenient pathway to the synthesis of stereodefined α,β-unsaturated enals or enones with the retention of the double-bond configuration.
J. Liu, S. Ma, Org. Lett., 2013, 15, 5150-5153.

A method for generating (E)-α,β-unsaturated aldehydes from Z- or E-allylic alcohols involves a Cu-catalyzed oxidation followed by an organocatalytic Z/E-isomerization with N,N-dimethylaminopyridine (DMAP).
D. Könning, W. Hiller, M. Christmann, Org. Lett., 2012, 14, 5258-5261.

A practical aerobic oxidation of propargylic alcohols using Fe(NO3)3•9H2O, TEMPO and sodium chloride in toluene at room temperature allows the conversion of propargylic alcohols to α,β-unsaturated alkynals or alkynones in good to excellent yields. This protocol can also be applied in industrial-scale production.
J. Liu, X. Xie, S. Ma, Synthesis, 2012, 44, 1569-1576.

Pd/C-catalyzed oxidative alkoxycarbonylation of terminal alkynes using alcohols in the presence of tetrabutylammonium iodide under CO/O2 gave α,β-alkynyl esters and unsymmetrical maleate esters in very good yields depending on the reaction conditions. The protocols eliminate the use of phosphine ligands and offer catalyst recovery. The catalyst was recycled up to six times without significant loss of catalytic activity.
S. T. Gadge, B. M. Bhanage, Synlett, 2013, 24, 981-986.

Allylic alcohols were oxidized into aldehydes or ketones in the presence of oxygen and Et3N using Pd(OAc)2 as catalyst. Diols with one allylic function were selectively oxidized, with one of the hydroxyl groups remaining untouched.
F. Batt, E. Bourcet, Y. Kassab, F. Fache, Synlett, 2007, 1869-1872.

Adsorbed [RuCl2(p-cymene)]2 on activated carbon is an efficient, environmentally attractive and highly selective catalyst for use in aerobic oxidations, hydrolytic oxidations and dehydrations. The heterogeneous catalyst was recovered quantitatively by simple filtration  and could be reused with minimal loss of activity.
E. Choi, C. Lee, Y. Na, S. Chang, Org. Lett., 2002, 4, 2369-2371.

An aerobic oxidation of primary and secondary alcohols to aldehydes and ketones using TEMPO-CuCl as catalyst in the ionic liquid [bmin][PF6] has been developed. The system needs no bubbling of O2 due to its good solubility in the ionic liquid. The resulting aldehydes (with no traces of carboxylic acids) and ketones can be extracted with organic solvents. The ionic liquid can be reused after washing with water and drying under high vacuum (8 runs for the oxidation of benzyl alcohol: yields of 72%, 70, 68, 70, 65, 64, 62, and 60).
I. A. Ansari, R. Gree, Org. Lett., 2001, 1507-1509.

A four-component system consisting of acetamido-TEMPO/Cu(ClO4)2/TMDP/DABCO in DMSO allows an efficient room-temperature aerobic alcohol oxidation of various alcohols into their corresponding aldehydes or ketones in good to excellent yields. The catalytic system can be recycled.
N. Jiang, A. J. Ragauskas, J. Org. Chem., 2006, 71, 7087-7090.

The system Cu(ClO4)2/acetamido-TEMPO/DMAP catalyses the room-temperature aerobic oxidation of primary alcohols to aldehydes in the ionic liquid [bmpy]PF6. The catalysts can be recycled and reused.
N. Jiang, A. J. Ragauskas, Org. Lett., 2005, 7, 3689-3692.

1 mol-% TEMPO and a catalytic amount of 1,3-dibromo-5,5-dimethylhydantoin and NaNO2 is a highly efficient catalytic system for the aerobic oxidations of benzylic alcohols in water.
R. Liu, C. Dong, X. Liang, X. Wang, X. Hu, J. Org. Chem., 2005, 70, 239-244.

Oxidation of alcohols to aldehydes and ketones were performed under atmospheric oxygen with a catalytic amount of V2O5 in toluene at 100°C. Secondary alcohols can be chemoselectively converted into ketones in the presence of primary hydroxy groups.
S. Velusamy, T. Punniyamurthy, Org. Lett., 2004, 6, 217-219.

An I2-catalyzed hydroxylation of β-dicarbonyl moieties using air as the oxidant under photoirradiation gives α-hydroxy-β-dicarbonyl compounds. With α-unsubstituted malonates, the hydroxylated dimerization product was afforded as the predominant product along with a minor product, α,α-dihydroxyl malonate.
C.-B. Miao, Y.-H. Wang, M.-L. Xing, X.-W. Lu, X.-Q. Sun, H.-T. Yang, J. Org. Chem., 2013, 78, 11584-11589.

An efficient method for the 2-hydroxylation of 1,3-diketones by using inexpensive atmospheric oxygen as an oxidant under transition-metal-free and ecofriendly conditions provides products in high yields.
Z. Li, T. Li, J. Li, L. He, X. Jia, J. Yang, Synlett, 2015, 26, 2863-2865.

An efficient and economical ligand-free palladium-based oxidation system using molecular oxygen as the sole oxidant enables the Tsuji-Wacker oxidation of terminal olefins and especially styrenes to methyl ketones. In addition, this system achieves a tandem Wacker oxidation-dehydrogenation sequence of terminal olefins to yield α,β-unsaturated ketones.
Y.-F. Wang, Y.-R. Gao, S. Mao, Y.-L. Zhang, D.-D. Guo, Z.-L. Yan, S.-H. Guo, Y.-Q. Wang, Org. Lett., 2014, 16, 1610-1613.

A general, highly selective asymmetric redox-relay oxidative Heck reaction using achiral or racemic acyclic alkenols and boronic acids delivers remotely functionalized arylated carbonyl products, with excellent enantioselectivity under mild conditions, bearing a range of useful functionality. The regioselectivity of the initial migratory insertion depends on the electronic nature of the boronic acid.
T.-S. Mei, E. W. Werner, A. J. Burckle, M. S. Sigman, J. Am. Chem. Soc., 2013, 135, 6830-6833.

The copper-catalyzed highly regioselective reaction of aryl alkyl alkynes and arylpropargylic alcohols with diaryliodonium salts gives α-arylketones in good yields under mild conditions. Depending on the internal alkyne substrate,  two different arylation-oxygenation pathways under different reaction conditions have been elaborated based on deuterated experiments, controlling experiments, and spectroscopic analysis of reaction intermediates.
Z.-F. Xu, C.-X. Cai, J.-T. Liu, Org. Lett., 2013, 15, 2096-2099.

A catalytic oxidative cleavage of 1,3-diketones enables the synthesis of the corresponding carboxylic acids by aerobic photooxidation with iodine under irradiation with a high-pressure mercury lamp.
N. Tada, M. Shomura, L. Cui, T. Nobuta, T. Miura, A. Itho, Synlett, 2011, 2896-2900.

An aerobic photooxidative cleavage of vicinal diols yields carboxylic acids using 2-chloroanthraquinone in the presence of photoirradiation with a high-pressure mercury lamp. This is a metal-free reaction in which molecular oxygen is used as the terminal oxidant.
Y. Matsusaki, T. Yamaguchi, N. Tada, T. Miura, A. Itoh, Synlett, 2012, 23, 2059-2062.

An efficient oxidation of various acetals, including open-chain acetals, 1,3-dioxanes and 1,3-dioxalanes, with molecular oxygen in the presence of catalytic amounts of N-hydroxy­phthalimide (NHPI) and Co(OAc)2 as co-catalyst gave esters.
B. Karimi, J. Rajabi, Synthesis, 2003, 2373-2377.

Natural sunlight and air are enable an efficient oxidation of α-aryl halogen derivatives to the corresponding α-aryl carbonyl compounds at room temperature through the combination of photocatalysis and organocatalysis. A plausible mechanism was proposed on the basis of the mechanistic studies.
Y. Su, L. Zhang, N. Jiao, Org. Lett., 2011, 13, 2168-2171.

A green, practical, convenient, and cheap copper-catalyzed oxidative coupling of aromatic alcohols and acetonitrile to β-ketonitriles involves a C-C coupling with loss of two hydrogen atoms from the corresponding two carbons, using oxygen as the terminal oxidant.
J. Shen, D. Yang, Y. Liu, S. Qin, J. Zhang, J. Sun, C. Liu, C. Liu, X. Zhao, C. Chu, R. Liu, Org. Lett., 2014, 16, 350-353.

N-hydroxyphthalimide (NHPI) catalyzes a metal-free, aerobic oxidative cleavage of olefins. This methodology avoids the use of toxic metals or overstoichiometric amounts of traditional oxidants, showing good economical and environmental advantages. Based on the experimental observations, a plausible mechanism is proposed.
R. Lin, F. Chen, N. Jiao, Org. Lett., 2012, 14, 4158-4161.

A Wacker-type oxidation of alkynes catalyzed by PdBr2 and CuBr2 allows an efficient access to 1,2-diketones using molecular oxygen. Under optimized conditions, various alkynes give 1,2-diketones in good yield. The mechanism of this reaction was preliminarily investigated by control experiments.
W. Ren, Y. Xia, S.-J. Ji, Y. Zhang, X. Wan, J. Zhao, Org. Lett., 2009, 11, 1841-1844.

A combination of copper powder and Selectfluor generates a cationic copper species that efficiently catalyze the formation of 1,2-diketones from alkynes under mild conditions with water and dioxygen as inexpensive and environmentally benign sources of oxygen.
W. Zhang, J. Zhang, Y. Liu, Z. Xu, Synlett, 2013, 24, 2709-2714

The presence of catalytic amounts of carbon tetrabromide enables an aerobic photooxidative cleavage of carbon-carbon triple bonds to carboxylic acids under photoirradiation.
T. Yamaguchi, T. Nobuta, Y. Kudo, S.-i. Hirashima, N. Tada, T. Miura, A. Itoh, Synlett, 2013, 24, 607-610.

Aerobic oxidation of deoxybenzoins is efficiently catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO) with air as the sole oxidant to give the corresponding benzils in excellent yields. The process has been successfully extended to a one-pot synthesis of quinoxalines from benzyl ketones and aromatic 1,2-diamines.
C. Qi, H. Jiang, L. Huang, Z. Chen, H. Chen, Synthesis, 2011, 387-396.

An efficient aerobic linear allylic C-H amination under palladium(II)/bis-sulfoxide/Brønsted base catalysis operates under operationally simple conditions (1 equiv of olefin, 1 atm O2 or air) with reduced catalyst loadings while providing higher turnovers and product yields than systems employing stoichiometric benzoquinone (BQ) as the terminal oxidant.
C. P. Pattillo, I. I. Strambeanu, P. Calleja, N. A. Vermeulen, T. Mizuno, M. C. White, J. Am. Chem. Soc., 2016, 138, 1265-1272.

An oxidative amidation of aromatic aldehydes in the presence of low loadings of phenazine ethosulfate as an inexpensive metal-free visible light photocatalyst proceeds at ambient temperature and uses air as the sole oxidant. The operationally easy procedure provides an economical, green, and mild alternative for the formation of amide bonds.
D. Leow, Org. Lett., 2014, 16, 5812-5815.

A Cu-catalyzed oxidative amidation-diketonization reaction of terminal alkynes leads to α-ketoamides. In this copper-catalyzed radical process, O2 not only participates as the ideal oxidant but also undergoes dioxygen activation under ambient conditions.
C. Zhang, N. Jiao, J. Am. Chem. Soc., 2010, 132, 28-29.

A copper-catalyzed aerobic oxidative cross-dehydrogenative coupling (CDC) of amines with α-carbonyl aldehydes leads to various α-ketoamides compounds. Many types of amines are tolerant in this transformation. Wide substrate scope, and the use of air as oxidant and initiator make this transformation highly efficient and practical.
C. Zhang, X. Zong, L. Zhang, N. Jiao, Org. Lett., 2012, 14, 3280-3283.

An efficient, mild Pd-catalyzed oxidative coupling of aromatic primary amines and alkenes under molecular oxygen provides a rapid access to (Z)-enamines with exceptional functional group tolerance and excellent regio- and stereoselectivity. The resultant enamines could be conveniently transformed into a series of N-containing heterocycles, thus illustrating its potential applications in synthetic and medicinal chemistry.
X. Ji, H. Huang, W. Wu, X. Li, H. Jiang, J. Org. Chem., 2013, 78, 11155-11162.

A clay-supported copper nitrate (Claycop) and a catalytic amount of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl enable an inexpensive and mild reagent system for the nitration of a wide variety of aromatic and aliphatic olefins. High conversions and exclusive E-selectivity, together with the environmentally benign nature of the Claycop reagent, make this a green method and an attractive alternative to established methods.
E. Begari, C. Singh, U. Nookaraju, P. Kumar, Synlett, 2014, 25, 1997-2000.

A copper-catalyzed decarboxylative coupling of sulfoximines with aryl propiolic acids enables the preparation of N-alkynylated sulfoximines. Various substituents on both the sulfoximidoyl moiety as well as the aryl group of the propiolic acid were tolerated.
D. L. Priebbenow, P. Becker, C. Bolm, Org. Lett., 2013, 15, 6155-6157.

Iodine/base-catalyzed aerobic photooxidation of 1,3-diketones under visible-light irradiation of fluorescent lamp enables a catalytic direct synthesis of 1,2-diketones.
N. Tada, M. Shomura, H. Nakayama, T. Miura, A. Itoh, Synlett, 2010, 1979-1983.

Pd(DMSO)2(TFA)2 as a catalyst enables a direct dehydrogenation of cyclohexanones and other cyclic ketones to the corresponding enones, using O2 as the oxidant. α,β-Unsaturated carbonyl compounds are versatile intermediates in the synthesis of pharmaceuticals and biologically active compounds. The substrate scope includes heterocyclic ketones and several natural-product precursors.
T. Diao, S. S. Stahl, J. Am. Chem. Soc., 2011, 133, 14566-14569.

Use of 4,5-diazafluorenone as an ancillary ligand for Pd(OAc)2 enables terminal alkenes to be converted to linear allylic acetoxylation products in good yields and selectivity under O2. Mechanistic studies have revealed that the ligand facilitates C-O reductive elimination from a π-allyl-PdII intermediate, thereby eliminating the requirement for benzoquinone as stoichiometric oxidant in this key catalytic step.
A. N. Campbell, P. B. White, I. A. Guzei, S. S. Stahl, J. Am. Chem. Soc., 2010, 132, 15116-15119.

A mild copper-catalyzed Chan-Lam-Evans type cross-coupling reaction enables a stereospecific and regioselective preparation of enol esters from carboxylate salts or carboxylic acids and potassium alkenyltrifluoroborate salts in the presence of oxygen, catalytic CuBr, DMAP and 4 Å molecular sieves. Overall, this method demonstrates carboxylic acids as suitable reaction partners for nondecarboxylative copper-catalyzed cross-couplings.
F. Huang, T. D. Quach, R. A. Batey, Org. Lett., 2013, 15, 3058-3061.

A Cu2O-catalyzed aerobic oxidative decarboxylative ammoxidation of phenylacetic acids and α-hydroxyphenylacetic acids enables the synthesis of various primary benzamides in good yields. This one-pot domino protocol combines decarboxylation, dioxygen activation, oxidative C-H bond functionalization, and amidation reactions.
Q. Song, Q. Feng, K. Yang, Org. Lett., 2014, 16, 624-627.

The use of low loadings of a silver NHC catalysts enables a mild, selective oxidation of alcohols to aldehydes or carboxylic acids in the presence of BnMe3NOH or KOH under dry air in excellent yield. The catalytic system can also be used for a one-pot synthesis of imines in excellent yield.
L. Han, P. Xing, B. Jiang, Org. Lett., 2014, 16, 3428-3431.

Imines and secondary amines were synthesized selectively by a Pd-catalyzed one-pot reaction of benzyl alcohols with primary amines. The reactions did not require any additives and were effective for a wide range of alcohols and amines.
M. S. Kwon, S. Kim, S. Park, W. Bosco, R. K. Chidrala, J. Park, J. Org. Chem., 2009, 74, 2877-2879.

Iron-catalyzed aerobic oxidative reactions of primary amines, secondary amines, benzylamines with anilines, and alcohols with amines in the presence of air as the economic and safe oxidant, provide several direct, practical, and greener approaches for the preparation of useful imines.
E. Zhang, H. Tian, S. Xu, X. Yu, Q. Xu, Org. Lett., 2013, 15, 2704-2707.

The use of photosensitive C70 for the catalytic oxidation of benzylamines to the corresponding imines enables faster reaction rates, lower catalyst loadings, and clean reactions with simple workup without chromatography, compared to C60 or other commonly used photosensitizers such as tetraphenylporphyrin (TPP). Singlet oxygen (1O2) and the superoxide radical anion (O2•–) act as important reactive species in this oxidation.
R. Kumar, E. H. Gleißner, E. G. V. Tiu, Y. Yamakoshi, Org. Lett., 2016,18, 184-187.

A base-mediated protocol enables the synthesis of imines and amines from N-phenylureas and alcohols in good yields under air. This protocol is as an efficient alternative to conventional methods for the synthesis of imines and amines.
D. K. T. Yadav, B. M. Bhanage, Synlett, 2014, 25, 1611-1615.

Cu-catalyzed aerobic oxidative three-component coupling of a terminal alkyne, secondary amine, and sulfonamide enables an efficient synthesis of amidines. The use of Cu(OTf)2 as catalyst produces amidines selectively via an initial oxidative coupling of the terminal alkyne with the secondary amine, followed by hydroamidation of the ynamine intermediate with the sulfonamide. Glaser-Hay alkyne homocoupling products are not observed.
J. Kim, S. S. Stahl, J. Org. Chem., 2015, 80, 2448-2454.

A general, efficient, and metal-free method for aerobic oxidation of primary benzylamines to the corresponding oximes in good yields is catalyzed by N,N′,N″-trihydroxyisocyanuric acid in the presence of acetaldoxime and water as solvent. This practical method uses air as economic and green oxidant, water as green solvent, and tolerates a wide range of substrates.
J. Yu, M. Lu, Synlett, 2014, 25, 1873-1878.

A mild, aerobic, catalytic synthesis of nitriles directly from alcohols and aqueous ammonia proceeds via a dehydrogenation cascade mediated by catalytic CuI, bpy, and TEMPO in the presence of oxygen. The substrate scope includes various functionalized aromatic and aliphatic alcohols. This protocol also enabled a one-pot synthesis of various biaryl heterocycles directly from commercially available alcohols.
W. Yin, C. Wang, H. Huang, Org. Lett., 2013, 15, 1850-1853.

In the presence of a catalytic amount of 4-AcNH-TEMPO, NaNO2, and HNO3, benzaldehydes underwent condensation with NH4OAc and a subsequent aerobic oxidation to produce nitriles selectively under O2. Aerobic oxidative conversion of a primary alcohol is also achieved.
J.-H. Noh, J. Kim, J. Org. Chem., 2015, 80, 11624-11628.

In the presence of catalytic copper(II) bromide, a direct α-amination of ketones, esters, and aldehydes takes place to produce synthetically useful α-amino-substituted motifs. The transformation is proposed to proceed via a catalytically generated α-bromo carbonyl species followed by nucleophilic displacement of the bromide by the amine, which delivers the α-amino carbonyl adduct while the catalyst is reconstituted.
R. W. Evans. J. R. Zbieg, S. Wu, W. Li, D. W. C. MacMillan, J. Am. Chem. Soc., 2013, 135, 16074-16077.

In an efficient Mn-catalyzed aerobic oxidative hydroxyazidation of olefins for synthesis of β-azido alcohols, an aerobic oxidative generation of azido radical is a key process. The reaction offers broad substrate scope, the use of an inexpensive Mn-catalyst, high efficiency, easy operation under air, and mild conditions at room temperature.
X. Sun, X. Li, S. Song, Y. Zhu, Y.-F. Liang, N. Jiao, J. Am. Chem. Soc., 2015, 137, 6059-6066.

Various tertiary β-trifluoromethyl alcohols can be synthesized in good yields without transition metal catalysts via a radical trifluoromethylation of alkenes using in situ generated peroxide in NMP under O2 as the radical initiator.
C. Liu, Q. Lu, Z. Huang, J. Zhang, F. Liao, P. Peng, A. Lei, Org. Lett., 2015, 17, 6034-6037.

Pd(II)-catalyzed ortho-hydroxylation of variously substituted benzoic acids under an athmospheric pressure of oxygen or air is achieved under nonacidic conditions. Labeling studies support a direct oxygenation of aryl C-H bonds with molecular oxygen.
Y.-H. Zhang, J.-Q. Yu, J. Am. Chem. Soc., 2009, 131, 14654-14655.

The use of flavin organocatalysts and a Hantzsch ester enabled a transition-metal-free Dakin oxidation fueled by molecular oxygen as the terminal oxidant. Catechols and electron-rich phenols are achieved with low catalyst loadings, in the presence of Hantzsch ester, and O2 or air as the stoichiometric oxidant source.
S. Chen, F. W. Foss, Jr, Org. Lett., 2012, 14, 5150-5153.

A general and efficient aerobic oxidative hydroxylation of arylboronic acids promoted by benzoquinone provides phenols in very good yields. The main advantages of this protocol are the use of water as solvent in the presence of a catalytic amount of benzoquinone under metal-free conditions.
G. Chen, X. Zeng, X. Cui, Synthesis, 2014, 46, 263-268.

In a useful synthesis of phenols from arylboronic acids, hydrogen peroxide is generated in situ by aerobic photooxidation using visible-light irradiation and easily handled 2-chloroanthraquinone as an organocatalyst. The mild, metal- and base-free conditions enable an environmentally benign approach to the synthesis of phenols from arylboronic acids.
K. Matsui, T. Ishigami, T. Yamaguchi, E. Yamaguchi, N. Tada, T. Miura, A. Itoh, Synlett, 2014, 25, 2613-2616.

Passerini three-component reaction under catalytic aerobic conditions allows the conversion of alcohols instead of aldehydes. The reaction of alcohols, isocyanides, and carboxylic acids in toluene in the presence of a catalytic amount of cupric chloride, NaNO2, and TEMPO afforded, under an oxygen atmosphere, the P-3CR adducts in good yields.
J. Brioche, G. Masson, J. Zhu, Org. Lett., 2010, 12, 1432-1435.

Oxidative ring expansion of methylenecyclopropanes with CAN under oxygen atmosphere was investigated. A facile conversion affording 2,2-diarylcyclobutanones occurred in good yields.
V. Nair, T. D. Suja, K. Mohanan, Synthesis, 2006, 2531-2534.

A new copper-catalyzed oxidative [3 + 2] cycloaddition of alkenes with anhydrides using oxygen as the sole oxidant affords γ-lactones in good to excellent yield. This catalyzed cyclization process has a broad substrate scope.
L. Huang, H. Jiang, C. Qi, X. Liu, J. Am. Chem. Soc., 2010, 132, 17652-17654.

Cu/nitroxyl catalysts promote a highly efficient and selective aerobic oxidative lactonization of diols under mild reaction conditions using ambient air as the oxidant. A Cu/ABNO catalyst system shows excellent reactivity with symmetrical diols and hindered unsymmetrical diols, whereas a Cu/TEMPO catalyst system displays excellent chemo- and regioselectivity for the oxidation of less hindered unsymmetrical diols.
X. Xie, S. S. Stahl, J. Am. Chem. Soc., 2015, 137, 3767-3770.

Several Pd-catalyzed oxidative cyclizations proceed in excellent yield under simple aerobic conditions. Importantly, this system provided entry into enatioselective catalysis with a readily available Pd-sparteine complex.
R. M. Trend, Y. K. Ramtohul, E. M. Ferreira, B. Stoltz, Angew. Chem. Int. Ed., 2003, 42, 2892-2895.

Enantioselective intramolecular oxidative amidation of alkenes has been achieved using a (pyrox)Pd(II)(TFA)2 as catalyst and O2 as the stoichiometric oxidant. The reactions proceed at room temperature in very good yields and with high enantioselectivity. Catalyst-controlled stereoselective cyclization reactions are demonstrated for a number of chiral substrates.
R. I. McDonald, P. W. White, A. B. Weinstein, C. P. Tam, S. S. Stahl, Org. Lett., 2011, 13, 2830-2833.

Use of a base-free Pd(DMSO)2(TFA)2 catalyst enables the synthesis of six-membered nitrogen heterocycles via a Wacker-type aerobic oxidative cyclization of alkenes. Various heterocycles, including morpholines, piperidines, piperazines and piperazinones, are accessible by this method.
Z. Lu, S. S. Stahl, Org. Lett., 2012, 14, 1234-1237.

An operationally simple and rapid copper-catalyzed three-component synthesis of trisubstituted N-aryl guanidines involving cyanamides, arylboronic acids, and amines is performed in the presence of K2CO3, a catalytic amount of CuCl2·2H2O, bipyridine, and oxygen (1 atm).
J. Li, L. Neuville, Org. Lett., 2013, 15, 6124-6127.

In the presence of oxygen and a small amount of AIBN as radical initiator, primary amines are oxidatively coupled to imines and tertiary amines are cyanated to α-aminonitriles. These metal-free aerobic oxidative coupling reactions may find applications in a wide range of green oxidation chemistry.
L. Liu, Z. Wang, X. Fu, C.-H. Yan, Org. Lett., 2012, 14, 5692-5695.

A dioxygenation of alkenes using molecular oxygen and a simple, readily prepared hydroxamic acid derivative in th presence of a radical initiator offers an alternative to common dioxygenation processes catalyzed by precious transition metals. This transformation capitalizes on the unique reactivity profile of hydroxamic acid derivatives in radical-mediated alkene addition processes.
B. C. Giglio, V. A. Schmidt, E. J. Alexanian, J. Am. Chem. Soc., 2011, 133, 13320-13322.

A copper-catalyzed aerobic decarboxylative sulfonylation of alkenyl carboxylic acids with sodium sulfinates offers an expedient strategy for stereoselective synthesis of (E)-alkenyl sulfones that are widely present in biologically active natural products and therapeutic agents. The transformation proceeds via a radical process and exhibits a broad substrate scope and good functional group tolerance.
Q. Jiang, B. Xu, J. Jia, A. Zhao, Y.-R. Zhao, Y.-Y. Li, N.-N. He, C.-C. Guo, J. Org. Chem., 2014, 79, 7372-7379.

A nickel-catalyzed hydroxysulfonylation of alkenes using sodium sulfinates under air enabled the selective synthesis of β-hydroxysulfones in good yields and suppressed the formation of β-ketosulfones. On the contrary, sulfonylation of alkynes with sodium sulfonates afforded only β-ketosulfones.
N. Taniguchi, J. Org. Chem., 2015, 80, 7797-7802.

In an unprecedented oxidative radical process, dioxygen as the solely terminal oxidant triggers an aerobic oxidative difunctionalization of terminal alkynes toward β-keto sulfones with high selectivity. IR experiments revealed that pyridine not only acts as a base to successfully surpress ATRA (atom transfer radical addition) process, but also plays a vital role in reducing the activity of sulfinic acids.
Q. Lu, J. Zhang, G. Zhao, Y. Qi, H. Wang, A. Lei, J. Am. Chem. Soc., 2013, 135, 11481-11484.

An efficient base-catalyzed [3 + 3] oxidative aromatization of α,β-unsaturated carbonyl compounds with dimethyl glutaconate under mild, metal-free conditions affords substituted benzenes in high to excellent yields with oxygen as oxidant and water as sole byproduct. In situ generation of the α,β-unsaturated carbonyl compounds from aldehydes and ketones enables a more convenient tandem [3 + 2 + 1] aerobic oxidative aromatization reaction.
A. Diallo, Y.-L. Zhao, H. Wang, S.-S. Li, C.-Q. Ren, Q. Liu, Org. Lett., 2012, 14, 5776-5779.

Pd-catalyzed intermolecular aerobic dehydrogenative aromatizations enable the arylation of amines with cyclohexanones and 2-cyclohexen-1-ones. Under optimized reaction conditions, primary and secondary amines are selectively arylated in good yields under an atmosphere of molecular oxygen.
S. A. Girard, X. Hu, T. Knauber, F. Zhou, M.-O. Simon, G.-J. Deng, C.-J. Li, Org. Lett., 2012, 14, 5606-5609.

A copper-mediated intermolecular annulation of alkyl ketones and β-nitrostyrenes enables a regioselective synthesis of multisubstituted furan derivatives in good yields.
M. Ghosh, S. Mishra, A. Hajra, J. Org. Chem., 2015, 80, 5364-5368.

A dual catalytic approach offers readily access to substituted heterocycle aldehydes via oxygen radical addition to vinyl-gold intermediates under Fe catalyst assistance. This system offers good functional group compatibility for the synthesis of substituted oxazole, indole, and benzofuran aldehydes.
H. Peng, N. G. Akhmedov, Y.-F. Liang, N. Jiao, X. Shi, J. Am. Chem. Soc., 2015, 137, 8912-8915.

An iron-catalyzed route for the regioselective synthesis of 1,3- and 1,3,5-substituted pyrazoles from the reaction of diarylhydrazones and vicinal diols allows the conversions of a broad range of substrates.
N. Panda, A. K. Jena, J. Org. Chem., 2012, 77, 9401-9406.

A convenient and efficient FeCl3/I2-catalyzed aerobic oxidative coupling of amidines and chalcones provides tetrasubstituted imidazoles in high regioselectivity and yields. The reaction offers good functional group tolerance, and mild reaction conditions.
Y. Zhu, C. Li, J. Zhang, M. She, W. Sun, K. Wan, Y. Wang, B. Yin, P. Liu, J. Li, Org. Lett., 2015, 17, 3872-3875.

A facile and versatile catalytic system involving copper catalyst, K3PO4 as the base, and O2 as the oxidant enables an efficient synthesis of 2,4,6-trisubstituted and 2,6-disubstituted 1,3,5-triazines and 1,3-disubstituted 1,2,4-triazoles from amidines with trialkylamines, DMSO, and DMF as the reaction partners, respectively. This protocol features an inexpensive catalyst, a green oxidant, good functional group tolerance, and high regioselectivity.
H. Huang, W. Guo, W. Wu, C.-J. Li, H. Jiang, Org. Lett., 2015, 17, 2894-2897.

A direct access to symmetrical and unsymmetrical 2,5-disubstituted [1,3,4]-oxadiazoles has been accomplished through an imine C-H functionalization of N-arylidenearoylhydrazide using a catalytic quantity of Cu(OTf)2. These reactions can be performed in air atmosphere and moisture making it exceptionally practical for application in organic synthesis.
S. Guin, T. Ghosh, S. K. Rout, A. Banerjee, B. K. Patel, Org. Lett., 2011, 13, 5976-5979.

Efficient palladium-catalyzed sequential isocyanide insertions into N-H and O-H bonds of hydrazides followed by oxidative annulation provide a convenient access to valuable 2-amino-1,3,4-oxadiazoles and their derivatives.
T. Fang, Q. Tan, Z. Ding, B. Liu, B. Xu, Org. Lett., 2014, 16, 2342-2345.

A highly efficient eosin Y catalyzed oxidative heterocyclization of semicarbazones was established under visible-light photoredox catalysis using CBr4 as a bromine source. The protocol renders a rapid, mild, and efficient access to valuable 5-substituted 2-amino-1,3,4-oxadiazoles in an operationally simple way utilizing visible light and atmospheric oxygen.
R. Kapoorr, S. N. Singh, S. Tripathi, L. D. S. Yadav, Synlett, 2015, 26, 1201-1206.

A convenient one-pot Cu(I)-catalyzed strategy gives trisubstituted α-carbonyl furans derivatives in good yields via (2-furyl) carbene complexes using air as the oxidant.
H. Cao, H. Zhan, J. Cen, J. Lin, Y. Lin, Q. Zhu, M. Fu, H. Jiang, Org. Lett., 2013, 15, 1080-1083.

A highly efficient carbon-carbon triple bond cleavage reaction of (Z)-enynols offered a new route to highly substituted butenolides through a gold(I)-catalyzed tandem cyclization/oxidative cleavage.
Y. Liu, F. Song, S. Guo, J. Am. Chem. Soc., 2006, 128, 11332-11333.

An unprecedented ruthenium(II)-catalyzed oxidative C-N coupling method enables a facile intramolecular synthesis of various synthetically challenging tri- and tetrasubstituted pyrazoles in the presence of oxygen as oxidant. The reaction demonstrates excellent reactivity, functional group tolerance, and high yields.
J. Hu, S. Chen, Y. Sun, J. Yang, Y. Rao, Org. Lett., 2012, 14, 5030-5033.

A one-pot, three-component coupling of aldehydes, 1,3-dicarbonyls, and diazo compounds as well as tosyl hydrazones enables an operationally simple and high yielding synthesis of polyfunctional pyrazoles. The reaction proceeds through a tandem Knoevenagel condensation, 1,3-dipolar cycloaddition, and transition metal-free oxidative aromatization reaction sequence utilizing molecular oxygen as a green oxidant.
A. Kamal, K. N. V. Sastry, D. Chandrasekhar, G. S. Mani, P. R. Adiyala, J. B. Nanubolu, K.  J. Singarapu, R. A. Maurya, J. Org. Chem., 2015, 80, 4325-4335.

A copper-catalyzed [3 + 2] cycloaddition/oxidation reaction of nitro-olefins with organic azides affords a broad range of 1,4(-NO2),5-trisubstituted 1,2,3-triazoles with high regioselectivities and in very good yields without elimination of HNO2.
Y. Chen, G. Nie, Q. Zhang, S. Ma, H. Li, Q. Hu, Org. Lett., 2015, 17, 1118-1121.

A copper-catalyzed reaction of acetophenones and 1,3-diaminopropane provides direct access to 2-arylpyridines. A range of electronically diverse acetophenones undergo this transformation, affording 2-arylpyridines in good yields.
L.-Y. Xi, R.-Y. Zhang, S. Liang, S.-Y. Chen, X.-Q. Yu, Org. Lett., 2014, 16, 5269-5271.

A convenient base-promoted reaction of 1-arylethylamines with ynones gives polysubstituted pyridines via direct β-C(sp3)-H functionalization of enaminones under metal-free conditions. This procedure features high regioselectivity, high efficiency, and environmental friendliness. Various polysubstituted pyridines were provided in high yields.
J. Shen, D. Cai, C. Kuai, Y. Liu, M. Wei, G. Cheng, X. Cui, J. Org. Chem., 2015, 80, 6584-6589.

A copper(II)-catalyzed tandem reaction between pyridine ketone and benzylamine proceeded via an efficient condensation-amination-oxidative dehydrogenation process, affording 1,3-diarylated imidazo[1,5-a]pyridines in excellent yields using clean O2 as an oxidant.
H. Wang, W. Xu, Z. Wang, L. Yu, K. Xu, J. Org. Chem., 2015, 80, 1856-1865.

A zinc iodide catalyzed reaction of 2-aminopyridines and α-amino carbonyl compounds in the presence of oxygen affords 3-aminoimidazo[1,2-a]pyridines in good yields.
X. Han, C. Ma, Z. Wu, G. Huang, Synthesis, 2016, 48, 351-356.

An operationally simple, atom-economic, palladium-catalyzed cyclization reaction of N-aryl imines, affords indoles via an oxidative linkage of two C-H bonds under mild conditions in the presence of oxygen. The process allows quick assembly of indole rings from inexpensive and readily available anilines and ketones and tolerates a broad range of functional groups.
Y. Wei, I. Deb, N. Yoshikai, J. Am. Chem. Soc., 2012, 134, 9098-9101.

An efficient oxidative protocol enables the synthesis of multisubstituted or fused tetracyclic benzimidazoles via a metal-free oxidative C-N coupling between the sp3 C-H and free N-H of readily available N1-benzyl/alkyl-1,2-phenylenediamines in the presence of oxygen and TEMPO.
D. Xue, Y.-Q. Long, J. Org. Chem., 2014, 79, 4727-4734.

An efficient strategy for the synthesis of 3-substituted 2-benzylindoles from stable and readily available o-allylanilines occurred via a regioselective 5-exo-trig intramolecular oxidative cycloisomerization using Pd(OAc)2 as catalyst and molecular oxygen as an oxidant. The reaction showed a broad substrate scope with good to excellent yields.
R. Nallagonda, M. Rehan, P. Ghorai, Org. Lett., 2014, 16, 4786-4789.

A copper-catalyzed one-pot multicomponent cascade reaction of 1-bromo-2-(2,2-dibromovinyl)benzenes with aldehydes and aqueous ammonia enables a selective synthetis of various indole derivatives. 3-Cyano-1H-indoles, 9H-pyrimido[4,5-b]indoles, or 9H-pyrido[2,3-b]indoles depending on the concentration of ammonia, the molar ratio of reagents, and the structural features of the aldehyde.
B. Li, S. Guo, J. Zhang, X. Zhang, X. Fan, J. Org. Chem., 2015, 80, 5444-5456.

Molecular iodine promoted an efficient synthesis of isatins from 2′-aminophenylacetylenes, 2′-aminostyrenes, and 2′-amino-β-ketoesters via oxidative amidation. The reaction involves iodination, followed by Kornblum oxidation, and intramolecular amidation in one pot.
G. Satish, A. Polu, T. Ramar, A. Ilangovan, J. Org. Chem., 2015, 80, 5167-5175.

The two discrete photochemical activation modes of (-)-riboflavin sequentially induce isomerization and cyclization by energy transfer (ET) and single-electron transfer (SET) activation pathways in an emulation of the coumarin biosynthesis pathway via a key photochemical EZ isomerization step. The ensuing SET-based cyclization eliminates the need for a prefunctionalized aryl ring.
J. B. Metternich, R. Gilmour, J. Am. Chem. Soc., 2016, 138, 1040-1045.

A heterogeneous cobalt oxide is an effective catalyst for aerobic dehydrogenation of various 1,2,3,4-tetrahydroquinolines to the corresponding quinolines in good yields under mild conditions. Other N-heterocycles are also successfully oxidized to their aromatic counterparts.
A. V. Iosub, S. S. Stahl, Org. Lett., 2015, 17, 4404-4407.

A simple and efficient method enables a direct synthesis of substituted quinolines from anilines and aldehydes through C-H functionalization, C-C/C-N bond formation, and C-C bond cleavage in the presence of air as an oxidant.
R. Yan, X. Liu, C. Pan, X. Zhou, X. Li, X. Kang, G. Huang, Org. Lett., 2013, 15, 4876-4879.

o-Quinone-based catalysts enable an oxidative dehydrogenation of tetrahydroquinolines to afford quinolines. Use of a Co(salophen) cocatalyst allows the reaction to proceed efficiently with ambient air at room temperature. The utility of the catalytic method is demonstrated in the preparation of a number of medicinally relevant quinolines.
A. E. Wendlandt, S. S. Stahl, J. Am. Chem. Soc., 2014, 136, 11910-11913.

A robust and regioselective palladium-catalyzed intermolecular aerobic oxidative cyclization of 2-ethynylanilines with isocyanides enables the synthesis of 4-halo-2-aminoquinolines with good yields and broad substrates scope. Furthermore, this process can be easily extended to synthesis of various 6H-indolo[2,3-b]quinolines via an intramolecular Buchwald-Hartwig cross-coupling reaction in a two-step one-pot manner.
B. Liu, H. Gao, Y. Yu, W. Wu, H. Jiang, J. Org. Chem., 2013, 78, 10319-10328.

A novel and efficient copper-catalyzed cascade method for the synthesis of quinazolines in good yields uses readily available substituted (2-bromophenyl)methylamines and amidine hydrochlorides as the starting materials, inexpensive CuBr as the catalyst, and economical and environment friendly air as the oxidant. The procedure underwent sequential intermolecular N-arylation, intramolecular nucleophilic substitution and aerobic oxidation.
Q. Liu, Y. Zhao, H. Fu, C. Cheng, Synlett, 2013, 24, 2089-2094.

CuCl/DABCO/4-HO-TEMPO as the catalysts and oxygen as the terminal oxidant enabled an efficient aerobic oxidative synthesis of 2-substituted quinazolines and 4H-3,1-benzoxazines from the one-pot reaction of aldehydes with 2-aminobenzylamines and 2-aminobenzyl alcohols, respectively.
B. Han, X.-L. Yang, C. Wang, Y.-W. Bai, T.-C. Pan, X. Chen, W. Yu, J. Org. Chem., 2012, 77, 1136-1142.

One-pot two-step cyanide-mediated sequential reactions of ortho-phenylenediamines with aldehydes under aerobic oxidation conditions afford 2-aminoquinoxalines in high yields. Various substrates, including aliphatic aldehydes bearing acidic α-protons, are applicable.
Y.-H. Cho, K.-H. Kim, C.-H. Cheon, J. Org. Chem., 2014, 79, 901-907.

Copper(I) catalysis enables a direct transannulation of N-heteroaryl aldehydes or ketones with alkylamines via Csp3-H amination in the presence of oxygen as the sole oxidant. This transformation provides a rapid and concise access to multifunctional imidazo[1,5-a]pyridines.
M. Li, Y. Xie, Y. Ye, Y. Zou, H. Jiang, W. Zeng, Org. Lett., 2014, 16, 6232-6235.

A set of benzimidazoles, 3H-imidazo[4,5-b]pyridines, purines, xanthines and benzothiazoles was readily prepared from (hetero)aromatic ortho-diamines or ortho-aminothiophenol and aldehydes using chlorotrimethylsilane in DMF as a promoter and water-acceptor agent, followed by oxidation with air oxygen.
S. V. Ryabukhin, A. S. Plaskon, D. M. Volochnyuk, A. A. Tolmachev, Synthesis, 2006, 3715-3726.

The 1H-indazole skeleton can be constructed by a [3 + 2] annulation approach from arynes and hydrazones. Under different reaction conditions, both N-tosylhydrazones and N-aryl/alkylhydrazones can be used to afford various indazoles.
P. Li, C. Wu, J. Zhao, D. C. Rogness, F. Shi, J. Org. Chem., 2012, 77, 3127-3133.

A copper-catalyzed highly selective oxidative coupling-annulation of 2-alkylazaarenes with terminal alkenes provides a simple, efficient, and atom-economic synthesis of indolizines in good yields.
J.-l. Liu, Y.-L. Liang, H.-s. Wang, Y.-m. Pan, Synlett, 2015, 26, 2024-2028.

A CuI-catalyzed aerobic oxidative synthesis of imidazo[1,2-a]pyridines from 2-aminopyridines and acetophenones is compatible with a broad range of functional groups. The reaction also enables the formation of alkenyl-substituted imidazoheterocycles by using unsaturated ketones as substrates. Preliminary mechanistic studies indicate that this reaction proceeds through a catalytic Ortoleva-King reaction.
Y. Zhang, Z. Chen, W. Wu, Y. Zhang, W. Su, J. Org. Chem., 2013, 78, 12494-12504.

A rapid, copper-catalyzed aerobic dehydrogenative cyclization of pyridines with ketone oxime esters enables an environmentally friendly synthesis of imidazo[1,2-a]pyridines.
H. Huang, X. Ji, X. Tang, M. Zhang, X. Li, H. Jiang, Org. Lett., 2013, 15, 6218-6221.

In a copper-catalyzed synthesis of benzo[d]isothiazol-3(2H)-ones and N-acyl-benzothiazetidine by intramolecular dehydrogenative cyclization, a new nitrogen-sulfur bond is formed by N-H/S-H coupling. The present reaction tolerates various functional groups and gives products in gram scale.
Z. Wang, Y. Kuninobu, M. Kanai, J. Org. Chem., 2013, 78, 7337-7342.

Copper-catalyzed double C-S bond formation enables a highly efficient synthesis of benzothiazoles from easily available N-benzyl-2-iodoanilines and potassium sulfide via a traditional cross-coupling and an oxidative cross-coupling reaction.
X. Zhang, W. Zeng, Y. Yang, H. Huang, Y. Liang, Org. Lett., 2014, 16, 876-879.

An aerobic visible-light driven photoredox catalytic formation of 2-substituted benzothiazoles through radical cyclization of thioanilides features C-H functionalization and C-S bond formation with no direct metal involvement except the sensitizer. In this reaction, visible-light is the driving force, molecular oxygen the terminal oxidant, and water the only byproduct.
Y. Cheng, J. Yang, Y. Qu, P. Li, Org. Lett., 2012, 14, 98-101.

A Cu(II)-catalyzed oxidative decarboxylation of phenylacetic acids and α-hydroxyphenylacetic acids enables the synthesis of various 2-aryl benzothiazoles in good yields from 2-unsubstituted benzothiazoles in the presence of oxygen as the sole oxidant. The reaction proceeds via Cu(II)-catalyzed decarboxylation, C-H bond oxidation, ring-opening, and condensation steps in one-pot and tolerates various functional groups.
Q. Song, Q. Feng, M. Zhou, Org. Lett., 2013, 15, 5990-5993.

A catalytic amount of iodine enables a metal-free synthesis of 2-aminobenzothiazoles from cyclohexanones and thioureas in the presence of molecular oxygen as the oxidant under mild conditions. Various 2-aminobenzothiazoles, 2-aminonaphtho[2,1-d]thiazoles, and 2-aminonaphtho[1,2-d]thiazoles were prepared in satisfactory yields.
J. Zhao, H. Huang, W. Wu, H. Chen, H. Jiang, Org. Lett., 2013, 15, 2604-2607.

N-Arylthioureas are converted to 2-aminobenzothiazoles via intramolecular C-S bond formation/C-H functionalization in the presence of an unusual cocatalytic Pd(PPh3)4/MnO2 system under an oxygen atmosphere at 80°C. This method eliminates the need for an ortho-halo substituted precursor, instead achieving direct functionalization of the ortho-aryl C-H bond.
L. L. Joyce, R. A. Batey, Org. Lett., 2009, 11, 2792-2795.

A Pd-catalyzed aerobic oxidation of o-aminophenols and isocyanides gives 2-aminobenzoxazoles and 3-aminobenzoxazines in good yields and a broad substrate scope. This methodology has the advantages of experimental simplicity, mild reaction conditions, and easily accessible starting materials. Furthermore, the synthesis of other types of useful nitrogen heterocycles has been achieved.
B. Liu, M. Yin, H. Gao, W. Wu, H. Jiang, J. Org. Chem., 2013, 78, 3009-3020.

Visible light efficiently mediates a mild intramolecular oxidative cyclization of o-hydroxy-N-aryl-N,N-dialkylformamidines leading to 2-aminobenzoxazole derivatives in excellent yields in the presence of only 1 mol% tris(2,2′-bipyridine)ruthenium(II) as a photoredox catalyst and air as terminal oxidant.
V. P. Srivastava, L. D. S. Yadav, Synlett, 2013, 24, 2758-2762.

Highly efficient conditions for the preparation of 3,3-disubstituted oxindoles by a formal C-H, Ar-H coupling of anilides have been identified using catalytic Cu(OAc)2•H2O with atmospheric oxygen as the reoxidant in mesitylene or toluene as solvent; no additional base is required.
J. E. M. N. Klein, A. Perry, D. S. Pugh, R. J. K. Taylor, Org. Lett., 2010, 12, 3446-3449.

An aerobic, iodine-catalyzed oxidative C(sp3)-H amination/C-N cleavage of tertiary amines affords a route to a wide range of quinazolines and quinazolinones in good to excellent yields via a domino ring annulation. The method is metal-free, peroxide-free, and operationally simple and represents a new avenue for multiple C-N bond formations.
Y. Yan, Y. Xu, B. Niu, H. Xie, Y. Liu, J. Org. Chem., 2015, 80, 5581-5587.

A domino C-H functionalization of glycine derivatives for the production of a series of quinolines was achieved under catalytic radical cation salt induced conditions. A mechanism is proposed, that includes a peroxyl radical cation, which is generated by the coupling between O2 and TBPA+•.
X. Jia, F. Peng, C. Qing, C. Huo, X. Wang, Org. Lett., 2012, 14, 4030-4033.

An efficient CuCl2-catalyzed coupling of nonfunctionalized tetrahydroisoquinolines with organozinc reagents under aerobic conditions proceeds in high yields under mild reaction conditions and is broadly applicable to a wide range of substrates. The reaction involves an iminium ion intermediate that is formed via a SET process.
T. Wang, M. Schrempp, A. Berndhäuser, O. Schiemann, D. Menche, Org. Lett., 2015, 17, 3982-3985.

A copper-catalyzed synthesis of quinazolinones from easily available 2-arylindoles and amines or ammonium provided various quinazolinones in very good yields. This simple and mild reaction tolerates a broad range of functional groups.
Y. Feng, Y. Li, G. Cheng, L. Wang, X. Cui, J. Org. Chem., 2015, 80, 7099-7107.

Readily available o-vinylphenols undergo a formal (5 + 2) cycloaddition to alkynes in the presence of catalytic amounts of [Cp*RhCl2]2 and Cu(OAc)2. The reaction generates highly valuable benzoxepine skeletons in a practical, versatile, and atom-economical manner. Using carbon monoxide instead of an alkyne as reaction partner leads to coumarin products of a formal (5 + 1) cycloaddition.
A. Seoane, N. Casanova, N. Quiñones, J. L. Mascareñas, M. Gulías, J. Am. Chem. Soc., 2014, 136, 650-652.

Molecular iodine catalyzes a metal-free oxidative coupling of 2-aminobenzamides with aryl methyl ketones to yield 2-aryl quinazolin-4(3H)-ones. The selectivity of the reaction strongly depends on the quantity of iodine.
S. Mohammed, R. A. Vishwakarma, S. B. Bharate, J. Org. Chem., 2015, 80, 6915-6921.

A highly efficient α alkylation of ketones with primary alcohols by the use of a recyclable palladium catalyst has been demonstrated.
M. S. Kwon, N. Kim, S. H. Seo, I. S. Park, R. K. Cheedrala, J. Park, Angew. Chem., 2005, 117, 7073-7075.

A general and mild protocol of oxygen-promoted Pd(II) catalysis allows a selective cross-couplings of alkenyl- and arylboron compounds with various olefins. Unlike most cross-coupling reactions, this new methodology works well even in the absence of bases, consequently averting undesired homo-couplings.
K. S. Yoo, C. H. Yoon, J. W. Jung, J. Am. Chem. Soc., 2006, 128, 16348-16393.

A mild and efficient Pd(II) catalysis leads to the formation of carbon-carbon bonds between various organoboron compounds and alkenes. The resultant Pd(0) species is reoxidized by molecular oxygen to Pd(II). This protocol promotes the desired Pd(II) catalysis, whereas the competing Pd(0) pathways (Heck or Suzuki) are retarded.
Y. C. Jung, R. K. Mishra, C. H. Yoon, K. W. Jung, Org. Lett., 2003, 5, 2231-2234.

A Pd-catalyzed oxidative cross-coupling reaction of arylboronic acids with α-diazoesters using molecular oxygen as the reoxidant gives E-α,β-diarylacrylates in good yields and very high E-to-Z selectivity.
Y.-T. Tsoi, Z. Zhou, A. S. C. Chan, W.-Y. Yu, Org. Lett., 2010, 12, 4506-4509.

Terminal alkynes can be directly cross-coupled with alkylzinc reagents in the presence of a Pd catalyst at room temperature with air as the oxidant. CO was found to be critical in gaining high chemical yields and selectivities. Good yields were obtained for a wide range of alkynes and alkylzinc reagents.
M. Chen, X. Zheng, W. Li, J. He, A. Lei, J. Am. Chem. Soc., 2010, 132, 4101-4103.

A facile and environmentally friendly synthetic method for a variety of symmetrical 1,3-diyne derivatives is based on a Pd/C-CuI-catalyzed homocoupling reaction of terminal alkynes. The reaction was efficiently catalyzed by an extremely low loading of Pd/C and CuI in the presence of molecular oxygen as the oxidant without any phosphine ligands and bases.
T. Kurita, M. Abe, T. Maegawa, Y. Monguchi, H. Sajiki, Synlett, 2007, 2521-2524.

A Pd-catalyzed Wacker-type oxidative cyclization under air allows the construction of 2-methylquinolines in good yields under mild conditions.
Z. Zhang, J. Tang, Z. Wang, Org. Lett., 2008, 10, 173-175.

A direct convergent two-component synthesis of quinolines from α,β-unsaturated ketones and o-aminophenylboronic acid derivatives is regiocomplementary to the traditional Skraup-Doebner-Von Miller synthesis and proceeds under basic rather than strongly acidic conditions.
J. Horn, S. P. Marsden, A. Nelson, D. House, G. G. Weingarten, Org. Lett., 2008, 10, 4117-4120.

Aerobic oxidation of deoxybenzoins is efficiently catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO) with air as the sole oxidant to give the corresponding benzils in excellent yields. The process has been successfully extended to a one-pot synthesis of quinoxalines from benzyl ketones and aromatic 1,2-diamines.
C. Qi, H. Jiang, L. Huang, Z. Chen, H. Chen, Synthesis, 2011, 387-396.

An efficient copper-catalyzed cascade reaction of (2-aminophenyl)methanols with aldehydes using the combination of cerium nitrate hexahydrate and ammonium chloride leads to a wide range of 2-substituted quinazolines in good yields. The method tolerates a various functional groups and represents a convenient and practical strategy for synthesis of 2-substituted quinazoline derivatives.
Z. Chen, J. Chen, M. Liu, J. Ding, W. Gao, X. Huang, H. Wu, J. Org. Chem., 2013, 78, 11342-11348.

An efficient method enables a synthesis of 4-amino-2-aryl(alkyl)quinazolines from readily available N-arylamidines and isonitriles via palladium-catalyzed intramolecular aryl C-H amidination by isonitrile insertion.
Y. Wang, H. Wang, J. Peng, Q. Zhu, Org. Lett., 2011, 13, 4596-4599.

Palladium-catalyzed oxidative cyclocarbonylation of 2-vinylphenols enables a direct synthesis of various coumarins in good yields in the presence of low pressures of CO, and air or 1,4- benzoquinone as the oxidant. The reaction conditions are attractive in terms of environmental considerations and operational simplicity.
J. Ferguson, F. Zeng, H. Alper, Org. Lett., 2012, 14, 5602-5605.

Cross-dehydrogenative C-N annulations and dealkylative C-N annulations of 2′-N-aryl/alkylaminoacetophenones and 2′-N,N-dialkylaminoacetophenones respectively in the presence of Cu(OAc)2·H2O, NaOAc and air gave isatins in good yields. However, on reaction with CuBr, 2′-N-benzylaminoacetophenones underwent selective oxidation at the benzylic position to provide the corresponding benzamides exclusively.
A. Ilanovan, G. Satish, Org. Lett., 2013, 15, 5726-5729.

An easily prepared recyclable TEMPO derived sulfonic salt catalyst, and mineral acids (NaNO2 and HCl) enable a selective aerobic oxidation of structurally diverse benzylic sp3 C-H bonds of ethers and alkylarenes to provide synthetically and biologically valued isochromanones and xanthones in good yields.
Z. Zhang, Y. Gao, Y. Liu, J. Li, H. Xie, H. Li, W. Wang, Org. Lett., 2015, 17, 5492-5495.

Ruthenium supported on alumina acts as an efficient heterogeneous catalyst for the oxidation of non-activated as well as activated amines to the corresponding nitriles or imines with 1 atm of dioxygen or air.
K. Yamaguchi, N. Mizuno, Angew. Chem. Int. Ed., 2003, 42, 1480-1483.

In the presence of an easily prepared supported ruthenium hydroxide catalyst, Ru(OH)x/Al2O3, various primary azides including benzylic, allylic, and aliphatic ones could be converted into the corresponding nitriles in good yields. The Ru(OH)x/Al2O3 catalyst could be further employed for synthesis of amides in water from benzylic or aliphatic primary azides.
J. He, K. Yamaguchi, N. Mizuno, J. Org. Chem., 2011, 76, 4552-4553.

RuCl3-catalyzed oxidative cyanation of tertiary amines with sodium cyanide under molecular oxygen at 60°C gives the corresponding α-aminonitriles in excellent yields. This reaction is clean and should be an environmentally benign and useful process.
S.-I. Murahashi, N. Komiya, H. Terai, T. Nakae, J. Am. Chem. Soc., 2003, 125, 15312-15313.

A green dehydrogenation of hydrazo compounds using basic alumina or KF/alumina under solvent-free conditions afforded azo compounds in good to excellent yields.
M. Mihara, T. Nakai, T. Iwai, T. Ito, T. Mizuno, Synlett, 2007, 2124-2126.

Oxidations of organic substrates such as sulfides, secondary amines, N-hydroxylamines, and tertiary amines with molecular oxygen in the presence of 5-ethyl-3-methyllumiflavinium perchlorate catalyst and hydrazine monohydrate in 2,2,2-trifluoroethanol occur highly efficiently to give the corresponding oxidized compounds in excellent yields.
Y. Imada, H. Iida, S. Ono, S.-I. Murahashi, J. Am. Chem. Soc., 2003, 125, 2868-2869.

A regioselective one-pot synthesis of substituted pyrazoles from N-monosubstituted hydrazones and nitroolefins gives products in good yields. A key nitropyrazolidine intermediate is characterized and a plausible mechanism is proposed.
X. Deng, N. S. Mani, Org. Lett., 2006, 8, 3505-3508.

Two general protocols for the reaction of electron-deficient N-arylhydrazones with nitroolefins allow a regioselective synthesis of 1,3,5-tri- and 1,3,4,5-tetrasubstituted pyrazoles. Studies on the stereochemistry of the key pyrazolidine intermediate suggest a stepwise cycloaddition mechanism.
X. Deng, N. S. Mani, J. Org. Chem., 2008, 73, 2412-2415.

A second-generation, water-soluble cobalt catalyst for the formation of trans-THF products via the Mukaiyama aerobic oxidative cyclization gives superior yields and enables greatly simplified purification compared to the previous catalysts.  Quarternization of the amino group of the ligand with MeI allows a simple, neutral water extraction.
C. Palmer, N. A. Morra, A. C. Stevens, B. Bajtos, B. P. Machin, B. L. Pagenkopf, Org. Lett., 2009, 11, 5614-5617.

An asymmetric 1,2-addition of alkyl groups to conjugated cyclic enones gave allylic alcohols with chiral quaternary centers. The resultant allylic alcohols are converted into epoxy alcohols with excellent diastereoselectivities. A semipinacol rearrangement provided α,α-dialkyl-β-hydroxy ketones with all-carbon chiral quaternary centers.
S.-J. Jeon, P. J. Walsh, J. Am. Chem. Soc., 2003, 125, 9544-9545.

Highly enantio- and diastereoselective one-pot procedures for the synthesis of epoxy alcohols involve either asymmetric addition of an alkylzinc reagent to an enal or asymmetric vinylation of an aldehyde with divinylzinc reagents. Exposure of the reaction mixtures to dioxygen and addition of catalytic titanium tetraisopropoxide yields epoxy alcohols with good to excellent yields.
A. E. Lurain, A. Maestri, A. R. Kelli, P. J. Carroll, P. J. Walsh, J. Am. Chem. Soc., 2004, 126, 13608-13609.

A. E. Lurain, A. Maestri, A. R. Kelli, P. J. Carroll, P. J. Walsh, J. Am. Chem. Soc., 2004, 126, 13608-13609.

The oxidation of substituted toluenes by molecular oxygen to the corresponding substituted benzoic acids using Co(C18H35O2)2/NH4Br or Co(OAc)2/NaBr/AcOH as catalysts in the presence of a radical initiator in non-acidic solvents was investigated.
F. Yang, J. Sun, R. Zheng, W. Qiu, J. Tang, M. He, Tetrahedron, 2004, 60, 1225-1228.

A methyl group at an aromatic nucleus is oxidized directly to the corresponding carboxylic acid in the presence of molecular oxygen and catalytic hydrobromic acid under photoirradiation.
S.-I. Hirashima, A. Itoh, Synthesis, 2006, 1757-1759.

β-Ketoesters can directly be transformed to the corresponding α-hydroxymalonic esters, tartronic esters, with molecular oxygen catalyzed by calcium iodide under visible light irradiation from a fluorescent lamp. This convenient tandem oxidation/rearrangement reduces consumption of energy, time, and solvents.
N. Kanai, H. Nakayama, N. Tada, A. Itoh, Org. Lett., 2010, 12, 1948-1951.

An oxidative coupling method for alkyne difunctionalization under metal-catalyst-free conditions affords various β-ketodithianes in very good yields with high regioselectivities. The reaction provides valuable dithianes with controlled formation of a new C-C bond and a C-O bond via a radical coupling pathway.
J. Lai, L. Tian, X. Huo, Y. Zhang, X. Xie, S. Tang, J. Org. Chem., 2015, 80, 5894-5899.

Pd(OAc)2 in the presence of a BIAN ligand is an efficient catalyst system for the base-free oxidative Heck reaction that outperforms the currently available catalysts for the more challenging substrates studied. The catalyst system is highly selective, and works at room temperature with dioxygen as the oxidant.

Arylations of electron-rich heteroatom-substituted olefins were performed with electron-rich arylboronic acids via palladium(II) catalysis. This mild protocol, which offers access to functionalized enamides, exploits oxygen gas for reoxidation and a stable 1,10-phenanthroline bidentate ligand to promote the palladium(II) regeneration and to control the regioselectivity.
M. M. S. Andappan, P. Nilsson, H. v. Schenck, M. Larhed, J. Org. Chem., 2004, 69, 5212-5218.

Palladium-catalyzed oxidative Heck coupling reaction of coumarins and arylboronic acids allows a direct synthesis of 4-arylcoumarins in good yields. The reaction also showed tolerance toward functional groups such as hydro, methoxy, diethylamino, nitro, and chloro groups.
Y. Li, Z. Qi, H. Wang, X. Fu, C. Duan, J. Org. Chem., 2012, 77, 2053-2057.

An efficient copper-catalyzed oxidative trifluoromethylation of terminal alkynes and aryl boronic acids in the presence of air is successfully achieved by adding both the substrate and a portion of CF3TMS slowly using a syringe pump to the reaction mixture.
X. Jiang, L. Chu, F.-L. Qing, J. Org. Chem., 2012, 77, 1251-1257.

The chemoselective ring opening of N-tosyl aziridines with aldehydes catalyzed by an N-heterocyclic carbene gave carboxylates of 1,2-amino alcohols. A plausible mechanism for this reaction is discussed.
Y.-K. Liu, R. Li, L. Yue, B.-J. Li, Y.-C. Chen, Y. Wu, L.-S. Ding, Org. Lett., 2006, 8, 1521-1524.

Oxidations of organic substrates such as sulfides, secondary amines, N-hydroxylamines, and tertiary amines with molecular oxygen in the presence of 5-ethyl-3-methyllumiflavinium perchlorate catalyst and hydrazine monohydrate in 2,2,2-trifluoroethanol occur highly efficiently to give the corresponding oxidized compounds in excellent yields.
Y. Imada, H. Iida, S. Ono, S.-I. Murahashi, J. Am. Chem. Soc., 2003, 125, 2868-2869.

5-Ethyl-3-methyl-2′,4′:3′,5′-di-O-methylenedioxy-riboflavinium perchlorate, which is readily derived from commercially available vitamin B2, exhibits high catalytic activity for the oxidation of organic sulfides under an oxygen atmosphere with the assistance of hydrazine hydrate as a reductant. This is an inexpensive, convenient, and environmentally benign method for the selective oxidative transformation of sulfides into sulfoxides.
Y. Imada, I. Tonomura, N. Komiya, T. Naota, Synlett, 2013, 24, 1679-1682.

An efficient CuSO4-catalyzed S-arylation of thiols with aryl and heteroaryl boronic acids at room temperature is established. A wide variety of thiols and arylboronic acids can be converted in the presence of CuSO4 as the catalyst, inexpensive 1,10-phen·H2O as the ligand, oxygen as oxidant, and EtOH as environment-friendly solvent.
H.-J. Xu, Y.-Q. Zhao, T. Feng, Y.-S. Feng, J. Org. Chem., 2012, 77, 2649-2658.

In an environmentally friendly, atom-economical, and step-economical oxidation, thiols are used as a synthon for the preparation of thioamides without the use of exogenous sulfur reagents.
X. Wang, M. Ji, S. Lim, H.-Y. Jang, J. Org. Chem., 2014, 79, 7258-7260.

Unsymmetrical diorgano-monosulfides, selenides, and tellurides can be synthesized by the coupling of dichalcogenides with aryl- or alkylboronic acids using a copper catalyst in air. The present reaction takes advantage of both organochalcogenide groups on the dichalcogenide.
N. Taniguchi, J. Org. Chem., 2007, 72, 1241-1245.

A cross-coupling reaction of arylboronic acids with KSCN salt to yield aryl thiocyanates is catalyzed by copper acetate in the presence of 4-methylpyridine serving both as ligand and base under 0.2 MPa of molecular oxygen. Various arylboronic acids were suitable under the reaction conditions.
N. Sun, H. Zhang, W. Mo, B. Hu, Z. Shen, X. Hu, Synlett, 2013, 24, 1443-1447.

A regio and anti-selective copper-catalyzed 1,2-hydroxysulfenylation of alkenes can be carried out by the use of disulfides and acetic acid. Reoxidation of intermediate sulfides by oxygen enables the use of both organosulfide groups of the disulfides.
N. Taniguchi, J. Org. Chem., 2006, 71, 7874-7876.

Alkenyl sulfones can be stereoselectively synthesized from alkenes or alkynes using sodium sulfinates in the presence of CuI-bpy as catalyst and oxygen. The reaction of alkenes gives (E)-alkenyl sulfones via anti addition of the sulfonyl cation followed by an elimination process. Furthermore, the employment of alkynes produces (E)-β-haloalkenyl sulfones in the presence of potassium halides.
N. Taniguchi, Synlett, 2011, 1308-1312.

Copper-catalyzed hydrosulfonylations of both terminal and internal alkynes can be carried out using sodium sulfinates in air. The procedure affords syn-selectively (E)-alkenyl sulfones in good yields.
N. Taniguchi, Synlett, 2012, 23, 1245-1249.

A mild, efficient, and general aromatization of Hantzsch 1,4-dihydropyridines with oxygen was realized at room temperature with 5 mol % of 9-phenyl-10-methylacridinium perchlorate as photocatalyst, which could be easily recovered and reused.
X. Fang, Y.-C. Liu, C. Li, J. Org. Chem., 2007, 72, 8608-8610.

In the presence of activated carbon, Hantzsch 1,4-dihydropyridines and 1,3,5-trisubstituted pyrazolines were aromatized with molecular oxygen to the corresponding pyridines and pyrazoles in excellent yields.
N. Nakamichi, Y. Kawashita, M. Hayashi, Synthesis, 2004, 1015-1020.

CuI-catalyzed coupling of 2-halobenzylamines with β-keto esters or 1,3-diketones in i-PrOH in the presence of of K2CO3 produced 1,2-dihydroisoquinolines as the cyclization products, which underwent smooth dehydrogenation under air atmosphere to afford substituted isoquinolines.
B. Wang, B. Lu, Y. Jiang, Y. Zhang, D. Ma, Org. Lett., 2008, 10, 2761-2763.

An intramolecular palladium(II)-catalyzed oxidative carbon-carbon bond formation under air in the presence of pivalic acid as the reaction solvent, instead of acetic acid, results in greater reproducibility, higher yields, and broader substrate scope. The reaction allows the conversion of both electron-rich and electron-deficient diarylamines.
B. Liégault, D. Lee, M. P. Huestis, D. R. Stuart, K. Fagnou, J. Org. Chem., 2008, 73, 5022-5028.

A mild and efficient domino reaction allows a regiospecific synthesis of polysubstituted furans in moderate yields via a copper(I)-catalyzed rearrangement/dehydrogenation oxidation/carbene oxidation sequence of 1,5-enynes in situ formed from alkynols and diethyl but-2-ynedioate.
H. Cao, H. Jiang, W. Yao, X. Liu, Org. Lett., 2009, 11, 1931-1933.

A mild, Pd(OAc)2-catalyzed regioselective cross-coupling between indoles and potassium aryltrifluoroarylborates gives 2-aryl indoles in moderate yields in the presence of Cu(OAc)2 in acetic acid at room temperature.
J. Zhao, Y. Zhang, K. Cheng, J. Org. Chem., 2008, 73, 7428-7431.

A copper(II)-catalyzed conversion of bisaryloxime ethers to 2-arylbenzoxazoles involves a cascade C-H functionalization and C-N/C-O bond formation under oxygen atmosphere.
M. M. Guru, M. A. Ali, T. Punniyamurthy, Org. Lett., 2011, 13, 1194-1197.

C-H activation of aryl triazene compounds followed by intramolecular amination in the presence of a catalytic amount of Pd(OAc)2 provides 1-aryl-1H-benzotriazoles at moderate temperature.
R. K. Kumar, M. A. Ali, T. Punniyamurthy, Org. Lett., 2011, 13, 2102-2105.

A copper-catalyzed one-pot procedure enables the synthesis of imidazo[1,2-a]pyridines with aminopyridines and nitroolefins using air as oxidant. This general reaction appears to be very suitable for the construction of various imidazo[1,2-a]pyridines.
R.-L. Yan, H. Yan, C. Ma, Z.-Y. Ren, X.-A. Gao, G.-S. Huang, Y.-M. Liang, J. Org. Chem., 2012, 77, 2024-2028.

Copper(I) bromide catalyzes a domino reaction of alkyl halides and anthranilamides under air to afford 2-substituted quinazolin-4(3H)-ones in good to excellent yields and with wide functional group tolerance. A mechanism via a four-step domino reaction is proposed.
H. Wei, T. Li, Y. Zhou, L. Zhou, Q. Zeng, Synthesis, 2013, 45, 3349-3354.

The use of arylhydrazines as aryl radical source and air as oxidant enables a transition-metal-free C-3-arylation of quinolin-4-ones in the presence of a base. The reaction proceeds smoothly at room temperature without either prefunctionalization or N-protection of quinoline-4-ones.
M. Ravi, P. Chauhan, R. Kant, S. K. Shukla, P. P. Yadav, J. Org. Chem., 2015, 80, 5369-5376.

N. Nakamichi, Y. Kawashita, M. Hayashi, Synthesis, 2004, 1015-1020.

A copper-catalyzed reaction under an atmosphere of air provides 1,2,4-triazole derivatives by sequential N-C and N-N bond-forming oxidative coupling reactions. Starting materials and the copper catalyst are readily available and inexpensive. A wide range of functional groups are tolerated.
S. Ueda, H. Nagasawa, J. Am. Chem. Soc., 2009, 131, 15080-15081.

S. Ueda, H. Nagasawa, J. Am. Chem. Soc., 2009, 131, 15080-15081.

A convenient, copper-catalyzed C-H and C-N bond activation enables an efficient and conceptually new method for oxidative amination of azoles with tertiary amines. This protocol can be performed in the absence of external base and only requires atmospheric oxygen as oxidant.
S. Guo, B. Qian, C. Xia, H. Huang, Org. Lett., 2011, 13, 522-525.

The iridium-catalyzed dehydrogenative cyclization of 2-aminobiphenyls proceeds smoothly in the presence of a copper cocatalyst under air as a terminal oxidant to yield N-H carbazoles. A similar catalytic system can also be used for a dimerization reaction of 2-aminobiphenyl involving 2-fold C-H/N-H couplings.
C. Suzuki, K. Hirano, T. Satoh, M. Miura, Org. Lett., 2015, 17, 1597-1600.

Treatment of chlorobis(methyldiphenylsilyl)methyllithium with various Grignard reagents and CuCN·2LiCl afforded 1,1-disilylalkylcopper species. Subsequent aerobic oxidation provided various acylsilanes in good yields. The preparation of 1-cyano-1-silylalkylcopper species via consecutive double 1,2-migration of alkyl and cyano groups is described.
J. Kondo, A. Inoue, Y. Ito, H. Shinokubo, K. Oshima, Tetrahedron, 2005, 61, 3361-3369.

Copper-catalyzed aerobic oxidative coupling of terminal alkynes with H-phosphonates affords alkynylphosphonates in high yields.
Y. Gao, G. Wang, L. Chen, P. Xu, Y. Zhao, Y. Zhou, L.-B. Han, J. Am. Chem. Soc., 2009, 131, 7956-7957.

A [Cu(OH)•TMEDA]2Cl2 catalyzed tandem reaction allows the synthesis of a series of sterically and electronically divergent phenacyl tertiary phosphine-boranes.
G. Kumaraswamy, G. V. Rao, A. N. Murthy, B. Sridhar, Synlett, 2009, 1180-1184.

A series of propargylic amides were transformed to the corresponding alkylideneoxazolines by a gold(I) catalyst. A subsequent autoxidation to hydroperoxides bearing the heteroaromatic oxazoles followed by reduction to the corresponding alcohols with sodium borohydride enables a highly efficient, and atom-economic access to a series of functionalized 2,5-disubstituted oxazoles.
A. S. K. Hashmi, M. C. B. Jaimes, A. M. Schuster, F. Rominger, J. Org. Chem., 2012, 77, 6394-6408.

An efficient copper-TBAF-catalyzed arylation of sulfoximines with arylsiloxanes in dichloromethane at room temperature affords the desired N-aryl sulfoximines in good to excellent yields under an oxygen atmosphere. This mild C-N bond formation complements the existing approaches due to the advantageous properties of arylsiloxanes such as availability, low toxicity, ease of handling, high stability, and environmental benignity.
J. Kim, J. Ok, S. Kim, W. Choi, P. H. Lee, Org. Lett., 2014, 16, 4602-4603.

A simple and efficient method for the preparation of thiophosphates from benzenethiols involves copper(I) iodide catalyzed coupling of thiols with H-phosphonates in the presence of triethylamine. The reaction proceeds effectively via an aerobic dehydrogenative coupling to afford the corresponding thiophosphates in good yields.
B. Kaboudin, Y. Abedi, J.-Y. Kato, T. Yokomatsu, Synthesis, 2013, 45, 2323-2327.