Categories: C-C Bond Formation > Arenes >
Alkenylation, Arylation
| Related: |
 |
 |
Name Reactions
|
Versatile Cross Coupling Methods: |
Recent Literature
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.
The Zweifel reaction is a powerful transition-metal-free alternative to the
Suzuki-Miyaura reaction for the synthesis of alkenes. This transition-metal-free
coupling process enables the coupling of Grignard reagents or organolithiums for
an enantiospecific synthesis of a wide variety of functionalized acyclic and
cyclic olefin products.
R. J. Armstrong, W. Niwetmarin, V. K. Aggarwal, Org. Lett.,
2017, 19, 2762-2765.
A Ni-catalyzed Hiyama coupling of aryl halides with cheap, nontoxic, and
stable vinyltrimethoxysilane as the vinyl donor proceeds under mild and
ligand-free conditions. The method provides a diverse variety of styrene
derivatives in high yields with excellent functional group compatibility.
S. Wei, Y. Mao, S.-L. Shi, Synlett, 2021,
32,
1670-1674.
A mild nickel-catalyzed reductive cross-coupling between (hetero)aryl
bromides and vinyl acetate provides a variety of vinyl arenes, heteroarenes, and
benzoheterocycles. Importantly, dimethyl isosorbide as solvent makes this
protocol more sustainable.
M. Su, X. Huang, C. Lei, J. Jin, Org. Lett., 2022, 24,
354-358.
A bench-stable, crystalline vinyl thianthrenium salt can be readily prepared
from ethylene gas at atmospheric pressure in one step and is broadly useful in
annulation chemistry of (hetero)cycles, N-vinylation of heterocyclic
compounds, and palladium-catalyzed cross-coupling reactions.
F. Juliá, J. Yan, F. Paulus, T. Ritter, J. Am. Chem. Soc.,
2021, 143, 12992-12998.
Diaryl-, divinyl-, and dialkylindium compounds undergo a palladium-catalyzed
cross-coupling reaction with aryl halides in aqueous THF to provide the
corresponding coupling product in excellent yield. A wide range of functional
groups are tolerated. The indium compounds can be generated from indium
trichloride and two equimolar amounts of a Grignard reagent.
K. Takami, H. Yorimitsu, H. Shinokubo, S. Matsubara, K. Oshima,
Org. Lett., 2001, 3, 1997-1999.
In Suzuki-Miyaura coupling, Z-alkenyl halides can easily undergo Z-to-E
isomerization, the extent of which is dictated mainly by the ligand on palladium.
Pd(P(o-Tol)3)2 as catalyst of choice leads to the
desired products under mild conditions and in high yields that, in most cases,
retain their Z-olefin geometry.
G.-P. Lu, K. R. Voigtritter, C. Cai, B. H. Lipshutz, J. Org. Chem., 2012,
77, 3700-3703.
A stereoconvergent, nickel-catalyzed Suzuki-Miyaura cross-coupling enables
the conversion of a wide range of alkenyl ethers and aryl boronic esters for the
synthesis of variously substituted styrene derivatives. A mixture of E/Z
isomers of alkenyl ethers can be employed, thereby circumventing the
stereodefined synthesis of starting materials.
G.-M. Ho, H. Sommer, I. Marek,
Org. Lett., 2019, 21, 2913-2917.
Cross-coupling reactions of vinyl ethers with aryl Grignard reagents are
efficiently catalyzed by anionic diarylrhodium complexes, generated in situ from
[RhCl(cod)]2 and the aryl Grignard reagents. In this catalytic system,
vinyl-O bonds were preferably cleaved over Ar-O or Ar-Br bonds.
T. Iwasaki, Y. Miyata, R. Akimoto, Y. Fujii, H. Kuniyasu, N. Kambe, J. Am. Chem. Soc., 2014,
136, 9260-9263.
Highly Stereoselective Hydrocarbation of Terminal Alkynes via Pt-Catalyzed
Hydrosilylation/Pd-Catalyzed Cross-Coupling Reactions
S. E. Denmark, Z. Wang,
Org. Lett., 2001, 3, 933-935.
The use of the σ-donating DMA solvent is crucial for high selectivity in a
simple, mild, and efficient Pd-catalyzed Heck reaction, that delivers (E)-styrenyl
products for electronically nonbiased olefin substrates bearing a range of
useful functionality in high yields. Further studies suggest that the catalyst
distinguishes between β-hydrogens on the basis of their relative hydridic
character.
E. W. Werner, M. S. Sigman, J. Am. Chem. Soc., 2011,
133, 9692-9695.
[Rh(cod)OH]2 catalyzes an olefination of aliphatic
aldehydes with arylboroxines in air and neutral conditions in the absense of
external ligands or additives to provide aryl olefins in an efficient manner
with a good functional group tolerance. The mechanism involves a Rh(I)-catalyzed
1,2-addition and a Rh(III)-catalyzed elimination.
Z. Zhang, J. Jia, F. Hu, Y. Xia, Org. Lett., 2023, 25,
3228-3233.
A B(C6F5)3-catalyzed E-selective
isomerization of readily accessible allyl silanes and subsequent Hiyama coupling
of the versatile alkenyl silane intermediates provide a broad range of styrene
derivatives.
B. A. Kustiana, R. L. Melen, L. C. Morrill, Org. Lett., 2022, 24,
8694-8697.
Low-toxicity chromium(II) chloride catalyzes very fast coupling reactions of
various (hetero)arylmagnesium reagents with N-heterocyclic halides,
aromatic halogenated ketones or imines, and alkenyl iodides at room temperature.
Remarkably, much lower amounts of homo-coupling side products are obtained
compared to related iron, cobalt, or manganese cross-couplings.
A. K. Steib, O. M. Kuzmina, S. Fernandez, D. Flubacher, P. Knochel, J. Am. Chem. Soc., 2013,
135, 15346-15349.
Aryl Grignard reagents react stereospecifically with alkenyl halides in the
presence of manganese chloride as catalyst to afford cross-coupled products in
good yields.
G. Cahiez, O. Gager, F. Lecomte, Org. Lett.,
2008,
10, 5255-5256.
Sarcosine is an excellent ligand for cobalt-catalyzed carbon-carbon
cross-coupling of Grignard reagents with allylic and vinylic bromides. The
system performs efficiently when phenyl and benzyl Grignards are coupled with
alkenyl bromides. Notably, previously unachievable Co-catalyzed coupling of
allylic bromides with Grignards to linearly coupled α-products was also realized.
R. Frlan, M. Sova, S. Gobec, G. Stavber, Z. Časar, J. Org. Chem.,
2015,
80, 7803-7809.
Aryl nonaflates are employed as electrophiles in the Pd-catalyzed cross-coupling
with tosylhydrazones affording highly substituted olefins. Addition of LiCl and
the presence of small amounts of water are required to accomplish the coupling
successfully. Under the optimized conditions, the reactions proceed with high
yield and also high stereoselectivity depending on the nature of the coupling
partners.
J. Barluenga, L. Florentino, F. Aznar, C. Valdes, Org. Lett., 2011,
13, 510-513.
A diastereodivergent hydroarylation of terminal alkynes allows highly
selective synthesis of both E and Z diastereoisomers of aryl
alkenes, from the same set of starting materials, using the same combination of
palladium and copper catalysts. The selectivity is controlled by the
stoichiometry of the alcohol additive. The reactions tolerates esters, nitriles,
alkyl halides, epoxides, carbamates, acetals, ethers, silyl ethers, and
thioethers.
M. K. Armstrong, M. B. Goodstein, G. Lalic, J. Am. Chem. Soc.,
2018,
140, 10233-10241.
A diastereodivergent hydroarylation of terminal alkynes allows highly
selective synthesis of both E and Z diastereoisomers of aryl
alkenes, from the same set of starting materials, using the same combination of
palladium and copper catalysts. The selectivity is controlled by the
stoichiometry of the alcohol additive. The reactions tolerates esters, nitriles,
alkyl halides, epoxides, carbamates, acetals, ethers, silyl ethers, and
thioethers.
M. K. Armstrong, M. B. Goodstein, G. Lalic, J. Am. Chem. Soc.,
2018,
140, 10233-10241.
A bimetallic
catalyst system composed of a group 4 metallocene difluoride and palladium dichloride
enables a reductive cross-coupling of alkynes and aryl halides to provide (E)-alkenes
in the presence of a hydrosilane and NaF. This reaction proceeds via an in situ generated alkenyl
metallocene intermediate derived from the group 4 metallocene difluoride.
K. Takahashi, H. Morishita, Y. Ogiwara, N. Sakai, J. Org. Chem., 2018, 83,
13734-13742.
A highly efficient palladium-catalyzed cross-coupling reaction of
alkenyldimethyl(2-pyridyl)silanes with organic halides has been developed. The
potentially occurring two reaction pathways (carbometalation and transmetalation)
were perfectly controlled by simply changing the additives.
K. Itami, T. Nokami, J.-i. Yoshida, J. Am. Chem. Soc., 2001,
123, 5600-5601.
A synthetically useful nonfluoride-activated, silicon-based, cross-coupling
reaction employs inexpensive, commercially available reagents. The successful
coupling of in situ generated silyloxides also demonstrates the mechanistically
fascinating duality of the silanol moiety as a prosthetic group for controlled
carbon-carbon bond formation and as an activator for the coupling.
S. E. Denmark, R. F. Sweis, J. Am. Chem. Soc., 2001,
123, 6439-6440.
The combination of palladium catalysis and iridium photocatalysis enables a
general catalytic anti-hydroarylation of electron-deficient internal
alkynes with a broad range of arylboronic acids. The reaction of ortho-substituted
boronic acids provides pharmaceutically relevant heterocyclic cores via a
cascade process.
J. Corpas, P. Mauleón, R. G. Arrayás, J. C. Carretero,
Org. Lett., 2020, 22, 6473-6478.
A multicatalytic isomerization/cross-coupling sequence enables a
stereoselective coupling of readily available alkenyl methyl ethers with various
Grignard reagents to provide highly substituted alkenes. A cationic iridium
catalyst for the stereoselective isomerization of allyl methyl ethers to methyl
vinyl ethers is compatible with a nickel catalyst for the subsequent
cross-coupling.
C. Romano, C. Mazet, J. Am. Chem. Soc.,
2018,
140, 4743-4750.
An aqueous rhodium-catalyzed coupling reaction of arylboronic acids and
styrenyl olefins provides Heck-type products. When an enolizable functionality
is present within the aromatic ring, the
addition-hydrolysis pathway occurs to give hydrophenylated compounds. The use of
water is crucial since no reaction occurs under analogous conditions in organic
solvents.
M. Lautens, A. Roy, K. Fukuoka, K. Fagnou, B. Martín-Matute, J. Am. Chem. Soc., 2001,
123, 5358-5359.
Hydrosilylation of an alkynylboronic ester enables a rapid and stereodefined
synthesis of MIDA-boryl vinylsilanes. Subsequent selective cross-couplings in a
two-step bidirectional sequence provide a rapid and high-yielding synthesis of
complex styrenes.
M. G. McLaughlin, C. A. McAdam, M. J. Cook, Org. Lett.,
2015,
17, 10-13.
A direct cobalt-catalyzed vinylation of various aromatic halides using
β-halostyrene proceeded smoothly with a total retention of the double bond
configuration in the presence of triphenylphosphine as ligand. This procedure
offers a new route to the stereoselective synthesis of functionalized stilbenes.
A. Moncomble, P. Le Floch, A. Lledos, C. Gosmini, J. Org. Chem., 2012,
77, 5056-5062.
The presence of FeCl3/CuTC enables an efficient coupling of
functionalized aryl Grignard reagents and 1-arylvinyl halides to access
1,1-diarylethylenes of biological interest. This bimetallic system proved to be
superior to the use of Fe or Cu catalyst alone. The synthetic utility of this
protocol is illustrated in the field of steroid chemistry.
A. Hamze, J.-D. Brion, M. Alami, Org. Lett., 2012,
14, 2782-2785.
A nickel-catalyzed addition of arylboron reagents to ketones provides olefins.
The neutral reaction conditions allow acidic protons of alcohols, phenols, and
malonates to be present, and fragile structures are also tolerated.
C. Lei, Y. J. Yip, J. S. Zhou, J. Am. Chem. Soc., 2017,
139, 6086-6089.
A palladium-catalyzed ligand-promoted C-C bond cleavage enables a
Mizoroki-Heck reaction of unstrained aryl ketones with acrylates/styrenes to
afford alkene products in very good yields.
M.-L. Wang, H. Xu, H.-Y. Li, B. Ma, Z.-Y. Wang, X. Wang, H.-X. Dai, Org. Lett., 2021, 23,
2147-2152.
A one-pot regioselective allene hydrosilylation/Pd(0)-catalyzed cross-coupling
protocol affords functionalized 1,1-disubstituted alkenes with excellent
regiocontrol. The regioselectivity of this hydroarylation is primarily governed
by N-heterocyclic carbene (NHC) ligand identity in the hydrosilylation
step and is preserved in the subsequent cross-coupling reaction.
Z. D. Miller, J. Montgomery, Org. Lett.,
2014,
16, 5486-5489.
A versatile, palladium-catalyzed cross-coupling reaction of hydrazones with aryl
halides in the absence of external ligand allows the synthesis of substituted
olefins, which are difficult to access from other traditional methods and are
not synthesized by employing similar coupling reactions. Application of the
present methodology is validated in tandem reaction of ketones to the
corresponding substituted olefins in a single pot experiment.
D. P. Ojha, K. R. Prabhu, J. Org. Chem., 2012,
77, 11027-11028.
A PdCl2(MeCN)2/Xphos/NaOtBu/F-benzene system
enabled the coupling of sterically hindered N-tosylhydrazones featuring
ortho/ortho′-substituents on the aromatic ring with various
substituted aryl halides in a sealed tube. This protocol has been applied
successfully to the synthesis of a xanthene derivative.
M. Roche, A. Hamze, O. Provot, J.-D. Brion, M. Alami, J. Org. Chem., 2013,
78, 445-454.
A stable palladium nanocatalyst was used for an efficient synthesis of
polysubstituted olefins from N-tosylhydrazones and aryl iodides. The
nanocatalyst can easily be recovered and reused without any apparent loss in
size and catalytic activity.
D. Ganapathy, G. Sekar, Org. Lett.,
2014,
16, 3856-3859.
Rhodium-catalyzed regioselective arylzincation of terminal allenes affords
synthetically useful functionalized allylzinc reagents, which can be protonated
or react with various electrophiles such as carbonyl compounds and acetonitrile.
Y. Yoshida, K. Murakami, H. Yorimitsu, K. Oshima, J. Am. Chem. Soc., 2010,
132, 8878-8879.
An aerobic boron Heck reaction with cyclobutene forms exclusively
linear 1-aryl-1,3-dienes using (hetero)arylboronic acids, or 1,3,5-trienes using
alkenylboronic acids, rather than typical Heck products (i.e., substituted
cyclobutenes).
N. J. McAlpine, L. Wang, B. P. Carrow, J. Am. Chem. Soc.,
2018,
140, 13634-13639.
A wide range of aryl and vinylic halides react with 1,1-dimethylallene and
potassium carbonate in the presence of Pd(dba)2 in N,N-dimethylacetamide
to provide dienes in very good yields. Tetramethylallene,
1-methyl-1-phenylallene, 1-methyl-3-phenylallene, and 1-cyclohexylallene also
react with aryl and vinylic halides to give diene products.
H.-M. Chang, C.-H. Cheng, J. Org. Chem., 2000,
65, 1767-1773.
A base-free rhodium-catalyzed Mizoroki-Heck reaction of potassium
aryltrifluoroborates with alkenes in the presence of acetone as green "oxidant"
constitutes an interesting alternative to conventional olefinations using aryl
halides thanks to the ready availability of organoboranes.
R. Martinez, F. Voica, J.-P. Genet, S. Darses, Org. Lett., 2007,
9, 3213-3216.
A highly selective Rh(I)-catalyzed defluorinative coupling of boronic acids with
(E)-β-monofluoroacrylates provides trisubstituted (Z)-alkene
products in excellent dr with an inversion of double bond geometry. Experimental
and computational studies established that Rh(I)-facilitated β-F elimination is
favored over competing β-H elimination and protodemetalation.
Y. Zong, Y. Tang, G. C. Tsui, Org. Lett.,
2022, 24, 6380-6385.
A gold-catalyzed intermolecular hydroarylation of propiolic acid with arylboronic acids is highly regioselective
and occurs at the less electrophilic carbon to afford α-aryl acrylic acids in
attractive yields. This carboxylic acid-directed arylation offers easy access to NSAID precursors.
K. S. Basha, R. Balamurugan, Org. Lett., 2023, 25,
4803-4807.
An I(III)-mediated skeletal reorganization of silyl enol ethers enables a
formal enone α-arylation. This metal-free transformation offeres mild conditions,
good yields, and high stereoselectivities for β-substituted enones.
B. S. Martins, D. Kaiser, A. Bauer, I. Tiefenbrunner, N. Maulide, Org. Lett., 2021, 23,
2094-2098.
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.
A. L. Gottumukkala, J. F. Teichert, D. Heijnen, N. Eisink, S. van Dijk, C.
Ferrer, A. van den Hoogenband, A. J. Minnaard, J. Org. Chem., 2011,
76, 2937-2941.
α-Haloalkenyl acetals react smoothly with (het)aryl boronic acids, aryl
boronates, or B-alkyl-9-borabicyclo[3.3.1]nonanes through Pd-catalyzed
Suzuki cross-coupling in very good yields. This mild protocol features a broad
substrate scope and good functional-group compatibility, and is easily scaled
up.
L. Zhang, Synlett, 2021, 32,
723-727.
In the TMSOTf-mediated catalytic carbocupration of ynoates, catalyst loadings as
low as 5 mol % readily allow for high yields and diastereoselectivities for a
series of aromatic Grignard reagents. A vicinally functionalization is possible
via initial TMSOTf-mediated catalytic carbocupration followed by a secondary
electrophilic capture of the TMS allenoate intermediate.
A. J. Mueller, M. P. Jennings, Org. Lett., 2007,
9, 5327-5329.
An (E)- and (Z)-stereocomplementary preparative method for α,β-disubstituted
α,β-unsaturated esters is performed via three general and robust reaction
sequences: Ti-Claisen condensation (formylation) of esters to give α-formyl
esters, (E)- and (Z)-stereocomplementary enol tosylation using
TsCl-N-methylimidazole-Et3N and LiOH, and stereoretentive
Suzuki-Miyaura cross-coupling.
H. Nakatsuji, H. Nishikado, K. Ueno, Y. Tanabe, Org. Lett., 2009,
11, 4258-4261.
A mild and efficient protocol for palladium-catalyzed oxidative Heck reactions
of arylboronic acids with both electron-rich and -deficient olefins works in the
absence of a base, oxygen, or other external oxidants. With a wide variety of
substrates tolerated, the method broadens the scope of palladium-catalyzed
coupling reactions.
J. Ruan, X. Li, O. Saidi, J. Xiao, J. Am. Chem. Soc., 2008,
130, 2424-2425.
The combination of [Ru(p-cymene)Cl2]2/triethylphosphine/lithium
carbonate catalyzes a coupling of aryl bromides with unprotected 2-arylacrylic
acids to form (Z)-diarylacrylic acids in high yields. The reaction
tolerates a wide range of functional groups. The vinylic C-H activation proceeds
via base-assisted cyclometalation rather than a Heck-type mechanism, which
explains its stereoselectivity.
F. Belitz, A.-K. Seitz, J. F. Goebel, Z. Hu, L. K. Goossen, Org. Lett.,
2022, 24, 3467-3470.
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.
A carboxylic-acid-directed oxidative Heck reaction enables a direct synthesis
of 4-aryl-3-butenoic acids in good yields.
S. Yang, L. Liu, Z. Zhou, Z. Huang, Y. Zhao, Org. Lett., 2021, 23,
296-299.
A copper(II)-catalyzed intermolecular three-component oxyarylation of allenes
using arylboronic acids as a carbon source and TEMPO as an oxygen source
proceeded under mild conditions with high regio- and stereoselectivity and
functional group tolerance.
T. Itoh, Y. Shimizu, M. Kanai, Org. Lett., 2014,
16, 2736-2739.
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.
In a highly regio- and stereoselective hydroarylation, hydroalkenylation, and
hydrobenzylation of ynol ethers, a Pd-catalyzed reductive addition of
organohalides, including aryl, alkenyl, and benzyl halides, in the presence of
2-propanol gives α,β- and β,β-disubstituted olefinic ethers in good yields.
W. Cui, J. Yin, R. Zheng, C. Cheng, Y. Bai, G. Zhu, J. Org. Chem., 2014,
79, 3487-3493.
A highly regio- and stereoselective coupling of (Z)-1,2-bis(aryl(alkyl)thio)alkenes
and Grignard reagents in the presence of a Ni catalyst under mild conditions
enables an efficient route for the synthesis of (Z)-vinylic sulfides. (Z)-vinylic
sulfides are important intermediates in the synthesis of tri- and
tetrasubstituted alkenes.
J. Chen, S. Chen, X. Xu, Z. Tang, C.-T. Au, R. Qiu, J. Org. Chem.,
2016,
81, 3246-3255.
An efficient Pd-catalyzed addition of boronic acids to silylacetylenes provides
β,β-disubstituted (E)- or (Z)-alkenylsilanes in good yields with
excellent regio- and stereoselectivity under mild reaction conditions. Moreover,
a sequential Pd-catalyzed boron addition/N-halosuccinimide-mediated
halodesilylation reaction results in a stereodivergent approach to
β,β-disubstituted alkenyl halides as versatile synthetic intermediates.
W. Kong, C. Che, J. Wu, L. Ma, G. Zhu, J. Org. Chem., 2014,
79, 5799-5805.
The palladium-catalyzed cross-coupling reaction of potassium
vinyltrifluoroborate with aryl electrophiles can generally be effected using 2
mol % of PdCl2 and 6 mol % of PPh3 as a catalyst system in
THF/H2O with Cs2CO3 as a base. Good yields are
obtained in the presence of various functional groups.
G. A. Molander, A. R. Brown, J. Org. Chem., 2006,
71, 9681-9686.
A Pd(0)-catalyzed Suzuki-Miyaura coupling reaction of aryl boronic acids with
vinyl tosylate provides access to styrene derivatives in good yields. The easily
accessible vinyl tosylate represents a stable and less toxic alternative to the
vinyl halides and the triflate/nonaflate derivatives. Furthermore, this
methodology was expanded using the similar and also readily available
2,2-difluorovinyl tosylate.
T. M. Gøgsig, L. S. Søbjerg, A. T. Lindhardt (neé Hansen), K. L. Jensen, T.
Skrydstrup, J. Org. Chem., 2008,
73, 3404-3410.
A variety of aromatic iodides and bromides undergo cross-coupling with
divinyltetramethyldisiloxane (DVDS) to give styrenes in good yields in the
presence of potassium trimethylsilanoate and catalytic amounts of Pd(dba)2.
Triphenylphosphine oxide is needed to extend catalyst lifetime.
S. E. Denmark, C. R. Butler, J. Am. Chem. Soc., 2008,
130, 3690-3704.
Fluoride-free cross-coupling reactions of alkenyltrialkoxysilanes with aryl
iodides, bromides, and chlorides are performed under ligand-free conditions with
low Pd loadings on water using sodium hydroxide as activator and tetra-n-butylammonium
bromide as additive at 120°C under conventional or microwave heating.
E. Alacid, C. Nájera, J. Org. Chem., 2008,
73, 2315-2322.
A novel bis-phenanthryl N-heterocyclic carbene (NHC) based palladium
acetate catalyst was effective for the coupling of various aryl and vinyl
chlorides with organoboron compounds. Hindered tri- and tetra-ortho
substituted products were efficiently produced. Benzyl chloride was also found
to be a useful coupling partner and trimethylboroxine was used to give
methylated products.
C. Song, Y. Ma, Q. Chai, C. Ma, W. Jiang, M. B. Andrus, Tetrahedron, 2005,
61, 7438-7446.
Efficient, stereospecific palladium(0)-catalyzed Suzuki-Miyaura
cross-couplings of potassium aryl- and heteroaryltrifluoroborates with
alkenyl bromides can generally be carried out using 2 mol % of palladium
catalyst and 3 equiv of base in toluene/H2O.
G. A. Molander, T. Fumagalli, J. Org. Chem., 2006,
71, 5743-5747.
A sequential hydroboration/Suzuki-Miyaura coupling of ynol ethers allows a
highly regio- and stereoselective synthesis of stereodefined β,β-disubstituted
alkenyl ethers. A number of functional groups are well-tolerated under the
reaction conditions. Furthermore, the reaction enables a facile entry to labile
diarylacetaldehydes by TFA-mediated hydrolysis of the β,β-disubstituted vinyl
ethers.
W. Cui, M. Mao, Z. He, G. Zhu, J. Org. Chem., 2013,
78, 9815-9821.
The reaction of acetanilides with symmetrical as well as unsymmetrical alkynes
in the presence of [{RuCl2(p-cymene)}2], pivalic
acid, and AgSbF6 in i-PrOH provides ortho-alkenylated
acetanilides in a highly regio- and stereoselective manner. The products can be
converted into ortho-alkenylated anilines in the presence of HCl.
R. Manikandan, M. Jeganmohan, Org. Lett., 2014,
16, 912-915.
A ruthenium-catalyzed chelation-assisted C-H bond activation of aromatic ketones
followed by reaction with olefins provides Heck-type products in good to
excellent yields with a high regio- and stereoselective manner.
K. Padala, M. Jeganmohan, Org. Lett., 2011,
13, 6144-6147.
Rh(III)-catalyzed olefination of N-sulfonyl imines using acrylates and
styrenes enables the synthesis of ortho-functionalized benzaldehydes via
a chelation assisted C-H olefination/in situ hydrolysis process.
T. Zhang, L. Wu, X. Li, Org. Lett., 2013,
15, 6294-6297.
Ruthenium-catalyzed oxidative C-H bond formation of N-methoxybenzamides
using an oxidizing directing group gives ortho-substituted Heck-type
products with acrylates in MeOH, whereas reactions with styrene (or
norbornadiene) in CF3CH2OH affords
3,4-dihydroisoquinolinones.
B. Li, J. Ma, N. Wang, H. Feng, S. Xu, B. Wang, Org. Lett., 2012,
14, 736-739.
A novel chelate-controlled intermolecular oxidative Heck reaction proceeds with
a wide range of nonresonance stabilized α-olefin substrates and organoboron
reagents to afford internal olefin products in good yields and outstanding
regio- and E:Z stereoselectivities. Pd-H isomerization, common in many
Heck reactions, is not observed under these mild, oxidative conditions.
J. H. Delcamp, A. P. Brucks, M. C. White, J. Am. Chem. Soc., 2008,
130, 11270-11271.
Addition of arylmagnesium bromides to aryl(alkyl)acetylenes gave high yields of
the corresponding alkenylmagnesium reagents in the presence of an iron catalyst
and a N-heterocyclic carbene ligand. Subsequent treatment with
electrophiles allows the formation of tetrasubstituted alkenes.
T. Yamagami, R. Shintani, E. Shirakawa, T. Hayashi, Org. Lett., 2007,
9, 1045-1048.
With certain substituent patterns, benzyl benzyl sulfone systems give
unexpectedly high Z-stereoselectivity in the Meyers variant of the
Ramberg-Bäcklund reaction. A range of sulfones were explored to rationalize this
unprecedented selectivity for Z-stilbene systems.
J. S. Foot, G. M. P. Giblin, A. C. Whitwood, R. J. K. Taylor, Org.
Biomol. Chem., 2005,
3, 756-763.
A mild, FeCl3-catalyzed addition of electron-rich arenes to
aryl-substituted alkynes gives 1,1-diaryl alkenes in good yields.
R. Li, S. R. Wang, W. Lu, Org. Lett., 2007,
9, 2219-2222.
Palladium-catalyzed cross-coupling reaction of 1,1-diboryl-1-alkenes with
aryl and alkenyl iodides proceeded stereoselectively to the corresponding
mono-coupled product as a single diastereomer. A subsequent coupling with
another aryl iodide afforded various triarylalkenes in their
stereochemically pure form.
M. Shimizu, C. Nakamaki, K. Shimono, M. Schelper, T. Kurahashi, T. Hiyama,
J. Am. Chem. Soc.,
2005,
127, 12506-12507.
Palladium-catalyzed Heck and Suzuki coupling reactions of arenediazonium
salts were performed at room temperature, without added base, under aerobic
conditions using a thiourea-based C2-symmetric ligand. The
reactions produced product in 4 h in good yield.
M. Dai, B. Liang, C. Wang, J. Chen, Z. Yang, Org. Lett., 2004,
6, 221-224.
A Pd(0)-catalyzed cross-coupling reaction of diazirines with aryl halides under
microwave irradiation affords substituted olefins in good yields via a migratory
insertion of a Pd carbene intermediate.
H. Jiang, H. Huang, H. Cao, C. Qi, Org. Lett., 2010,
12, 5561-5563.
PdCl2(MeCN)2 in combination with dppp is an efficient
catalyst for the coupling of sterically hindered N-arylsulfonylhydrazones
with aryl halides providing a flexible and convergent access to tetrasubstituted
olefins related to iso-combretastatin A4 in good yields.
E. Brachet, A. Hamze, J.-F. Peyrat, J.-D. Brion, M. Alami, Org. Lett., 2010,
12, 4042-4045.
TsCl coupled with NMI forms a highly
reactive N-sulfonylammonium intermediate. β-Ketoesters undergo (E)-selective
tosylation using TsCl-NMI-Et3N and (Z)-selective tosylation using TsCl-NMI-LiOH
in good yield. Stereoretentive Negishi and Sonogashira
couplings using enol tosylates proceed successfully to give trisubstituted
α,β-unsaturated esters.
H. Nakatsuji, K. Ueno, T. Misaki, Y. Tanabe, Org. Lett., 2008,
10, 2131-2134.
The employment of hydrophobic ionic liquids dramatically enhanced the
activity of metal triflates in Friedel-Crafts alkenylations of aromatic
compounds with various alkyl- and aryl-substituted alkynes.
C. E. Song, D.-U. Jung, S. Y. Choung, E. J. Roh, S.-G. Lee, Angew. Chem.,
2004,
116, 6309-6311.
A variety of organolithiums are added to terminal and 2,2-disubstituted epoxides
in the presence of LTMP to generate alkenes in a completely regio- and highly
stereoselective manner. Arylated alkenes, dienes, allylsilanes, and enynes are
accessed using this procedure.
D. M. Hodgson, M. J. Fleming, S. J. Stanway, J. Org. Chem., 2007,
72, 4763-4773.
A stereoselective arylation and vinylation of alkenes without transition-metal
catalysts takes place through an interesting NBS-promoted semipinacol
rearrangement under mild conditions and a subsequent unusual NaOH-mediated Grob
fragmentation.
D.-Y. Yuan, Y.-Q. Tu, C.-A. Fan, J. Org. Chem., 2008,
73, 7797-7799.
The PdCl2/PtBu3 catalytic system with copper(I)
iodide and cesium fluoride in DMF is most effective for coupling aryl bromides,
while Pd(PPh3)4 is optimal when coupling iodides and
triflates. The combination of copper(I) iodide and cesium fluoride should allow
the synthesis of sterically hindered systems and promotes electronically
disfavored coupling reactions.
S. P. H. Mee, V. Lee, J. E. Baldwin, Angew. Chem. Int. Ed., 2004,
43, 1132-1136.
A Pd(PPh3)4-catalyzed reaction between α-diazocarbonyl
compounds and arylboronic acids leads to cross-coupled products in good yields.
C. Peng, Y. Wang, J. Wang, J. Am. Chem. Soc., 2008,
130, 1566-1567.
A regio- and stereoselective rhodium-catalyzed reaction of propargylic alcohols
with boronic acids enables the synthesis of trisubstituted allylic alcohols. The
utility of these synthons is demonstrated in a convenient synthesis of indenes
and quinolines.
J. Panteleev, R. Y. Huang, E. K. J. Lui, M. Lautens, Org. Lett., 2011,
13, 5314-5317.
A copper-catalyzed highly anti-selective radical 1,2-alkylarylation of
terminal alkynes with aryl boronic acids and alkyl bromides providesg facile
access to various stereodefined trisubstituted alkenes in high yield under mild
reaction conditions. The reaction exhibits high compatibility with a wide range
of terminal alkynes and diverse aryl boronic acids.
J.-B. Tang, J.-Q. Bian, Y.-S. Zhang, Y.-F. Cheng, H.-T. Wen, Z.-L. Yu, Z.-L.
Yu, Z.-L. Li, Q.-S. Gu, G.-Q. Chen, X.-Y. Liu, Org. Lett.,
2022, 24, 2536-2540.
Cycloadditions of Diels-Alder dienophiles containing linked enyne sites, each
substituted with activating groups, occurred specifically at the acetylenic
center. A remote acrylyl group bound to the olefinic site totally dominated the
regiochemical course of the cycloaddition. Explanations for these findings at
the computational level are provided.
M. Dai, D. Sarlah, M. Yu, S. J. Danishefsky, G. O. Jones, K. N. Houk, J. Am. Chem. Soc., 2007,
129, 645-657.
Synthesis of Styrenes Using Ruthenium-Catalyzed Ring-Closing Enyne
Metathesis
K. Yoshida, Y. Shishikura, H. Takahashi, T. Imamoto, Org. Lett.,
2008,
10, 2777-2780.
Air-stable palladium complexes with phosphinous acid ligands serve as
efficient catalysts for various cross-coupling reactions of vinyl and aryl
chlorides with arylboronic acids, arylzinc reagents, and thiols.
G. Y. Li, J. Org. Chem., 2002, 67, 3643-3650.
The reaction of organocerium reagents, generated in situ from aryl and
heteroaryl lithium compounds, with cycloalkanones proceeds cleanly to provide
alkoxides. Addition of MsCl or SOCl2 with DBU gave aryl-substituted
cycloalkenes in good yields. A short total synthesis of (±)-laurokamurene B is
described.
J. Tallineau, G. Bashiardes, J.-M. Coustard, F. Lecornué, Synlett, 2009,
2761-2764.
Highly reactive zinc metal was readily prepared by electrolysis of a DMF
solution containing naphthalene and a supporting electrolyte in a
one-compartment cell fitted with a platinum cathode and a zinc anode. This
reactive zinc was used for efficient transformation of ethyl 2-bromoacrylate
into the corresponding organozinc compound, which was reacted with various
aryl iodides in the presence of palladium catalyst to give ethyl
2-arylpropenoates in high yields.
A. A. Jalil, N. Kurono, M. Tokuda, Synthesis,
2002, 2681-2686.
4-Substituted 1,2-oxaborol-2(5H)-ols were prepared through
copper-catalyzed carbomagnesation of propargyl alcohol, followed by the
transmetallation of magnesium to boron in a one-pot procedure. The
Suzuki-Miyaura cross-coupling of these new 2,2-disubstituted alkenylboronic
acids with aryl halides afforded stereodefined 2,3-disubstituted allyl
alcohols in good to excellent yields.
G.-H. Fang, Z.-J. Yan, M.-Z. Deng,
Synthesis, 2006, 1148-1154.
N-Vinylpyridinium and -trialkylammonium tetrafluoroborate salts represent
a new class of electrophilic coupling partner for Pd(0)-catalyzed Suzuki
cross-coupling reactions with various boronic acids in high yields. The
crystalline, air-stable, and nonhygroscopic salts are easily prepared from
activated acetylenes and pyridinium or trialkylammonium tetrafluoroborates.
K. R. Buszek, N. Brown, Org. Lett., 2007,
9, 707-710.
A Pd-catalyzed hydrogenation of potassium
(3,3,3-trifluoroprop-1-yn-1-yl)trifluoroborate provides either the (Z)-
or (E)-isomer of the vinylborate in >98% purity. Coupling with bromo- and
iodoarenes provides a variety of (Z)- or (E)-β-trifluoromethylstyrenes.
Also, a safe synthesis of the alkynyltrifluoroborate has been described.
P. V. Ramachandran, W. Mitsuhashi, Org. Lett.,
2015,
17, 1252-1255.
Lewis-acid catalysts such as AlMe3, AlMe2Cl, and BPh3 significantly improve
the efficiency of the nickel-catalyzed aryl- and alkenylcyanation of alkynes.
Electron-rich cyanides, which exhibit poor reactivity in the absence of Lewis
acids, readily undergo the arylcyanation reaction under the newly disclosed
conditions.
Y. Nakao, A. Yada, S. Ebata, T. Hiyama, J. Am. Chem. Soc., 2007,
129, 2428-2429.
(E)- or (Z)-trisubstituted α,β-unsaturated esters have
been prepared in three steps from N-protected glycine. The key step is the
highly selective enol tosylation of γ-amino β-keto esters followed by an
effective Suzuki-Miyaura coupling reaction with a variety of aryl boronic
acids.
J. Baxter, D. Steinhuebel, M. Palucki, I. W. Davies, Org. Lett.,
2005,
7, 215-218.
1,1-diarylpropadienes and 1,3-diarylpropynes can be prepared by the
sequential lithiation of 1-aryl-1-propynes, transmetalation, and the
corresponding Pd(0)-catalyzed cross-coupling with aryl halides.
S. Ma, Q. He, X. Zhang, J. Org. Chem., 2005,
70, 3336-3338.
Stereospecific coupling reactions of readily available alkenylsilanes have
been developed.
S. E. Denmark, J. Am. Chem. Soc., 1999,
121, 5821-5822.
A mild, stereospecific cross-coupling of unsymmetrical
1,4-bissilyl-1,3-butadienes has been developed. A selective cross-coupling
under mildly basic conditions afforded 4-aryl-1,3-dienylsilanes in excellent
yield for a wide range coupling partners. The subsequent cross-coupling of
the 4-aryl-1,3-dienylsilanes could be effected cleanly by the action of TBAF
with electron-rich or electron-poor halides.
S. E. Denmark, S. A. Tymonko, J. Am. Chem. Soc.,
2005,
127, 8004-8005.
The rhodium-catalyzed reaction of aryl boronic acids with internal alkynes
and acrylates in water gives the domino coupling products. The reaction
demonstrates that water offers the possibility to discover novel
transformations.
T. Kurahashi, H. Shinokubo, A. Osuka, Angew. Chem. Int. Ed., 2006,
45, 6336-6338.
Privileged allylic amine structures can be constructed in a regioselective,
stereoselective, and diversity-oriented manner by a novel
palladium-catalyzed four-component assembly based on allenylboronate
platform. A short synthesis of rolipram is also demonstrated.
K. Tonogaki, K. Itami, J.-I. Yoshida, J. Am. Chem. Soc.,
2006,
128, 1464-1465.
Homoallylic α-amino esters and amines were prepared via a Pd(II)-catalyzed
coupling of 1,2-nonadiene and boronic acids with ethyl iminoacetate or aliphatic,
aromatic, and heteroaromatic imines.
C. D. Hopkins, H. C. Malinakova, Org. Lett., 2006,
8, 5971-5974.
A mild, Pd/C-catalyzed Suzuki-Miyaura coupling of 2-iodocycloenones with
arylboronic acids is described. Notably, the procedure features inexpensive
reagents, reactions under air, and solvents with low toxicity. In addition,
the Pd/C could be reused at least five times.
F.-X. Felpin, J. Org. Chem., 2005,
70, 8575-8578.
Monofluorovinyl tosylate is a practical vinyl fluoride building block to couple
with various arylboronic acids in the presence of a palladium catalyst. A high
stereoselectivity in the synthesis of 2-aryl-1-fluoroethene derivatives was
achieved. This approach is also applicable to the synthesis of
2,2-diaryl-1-fluoroethenes in good yields.
H. Zhang, C.-B. Zhou, Q.-Y. Chen, J.-C. Xiao, R. Hong, Org. Lett., 2011,
13, 560-563.
A gem-difluoroolefination of trifluoroacetaldehyde N-triftosylhydrazone
with organoboronic acids - including alkylboronic acids - is operationally
simple, free of transition metals, and suitable for a broad range of substrates.
Moreover, the utility of the products was demonstrated by further conversion of
the gem-difluorovinyl group.
Y. Ma, B. R. P. Reddy, X. Bi,
Org. Lett., 2019, 21, 9860-9863.
A highly diastereoselective rhodium(I)-catalyzed C-F bond functionalization
of gem-difluoroalkenes with arylboronic acids provides valuable
monofluoroalkenes. A Rh(I)/BINAP catalytic system enables the C-F bond arylation
of both trisubstituted β,β-difluorostyrenes and tetrasubstituted
β,β-difluoroacrylates in >99:1 dr via a migratory insertion/β-F elimination
mechanism.
H. Tan, Y. Zong, Y. Tang, G. C. Tsui, Org. Lett., 2023, 25,
877-882.
An efficient Pd-catalyzed stereoselective vinyltrifluoromethylation of aryl
halides, through decarboxylative cross-coupling with 2-(trifluoromethyl)acrylic
acid offers ready availability of the starting materials, high level of
functional group tolerance, and excellent E/Z selectivity. This
protocol is a safe and operationally convenient strategy for an efficient
synthesis of vinyltrifluoromethyl derivatives.
S. Kathiravan, I. A. Nicholls, Org. Lett.,
2015,
17, 1874-1877.
An operationally simple Pd-catalyzed three component reaction involving terminal
alkynes, boronic acids, and perfluoroalkyl iodides gives trisubstituted
perfluoroalkenes in a highly regio- and stereocontrolled manner by simultaneous
additions across the triple bond in a radical-mediated process. The reaction is
broad in scope and tolerates many functional groups.
Z. Li, A. García-Domínguez, C. Nevado, J. Am. Chem. Soc., 2015,
137, 11610-11613.
A cobalt-catalyzed ynamide carbozincation provides diverse 3-aryl enamides with
mild reaction conditions and good functional-group tolerance. This reaction
displays an excellent regio- and total stereoselectivity. Moreover, this
approach allows the selective synthesis of biologically relevant
3,5-disubstituted oxazolone frameworks.
R. Sallio, M. Corpet, L. Habert, M. Durandetti, C. Gosmini, I. Gillaizeau, J. Org. Chem.,
2017, 82, 1254-1259.
The use of a palladium(II) acetate-organophosphine catalyst system enables an
efficient coupling of (1-bromovinyl)phosphonates with aryl boronic acids. A wide
range of (1-arylvinyl)phosphonates were prepared in very good yields. The
protocol can be effectively scaled up and even allows the use of a
(1-chlorovinyl)phosphonate as the electrophilic coupling partner.
Y. Fang, L. Zhang, X. Jin, J. Li, M. Yuan, R. Li, H. Gao, J. Fang, Y. Liu,
Synlett, 2015, 26, 980-984.
α-Phosphonovinyl tosylates can be coupled efficiently with a range of
arylboronic acids to provide α-arylethenylphosphonates. The unprecedented
procedure exhibits excellent functional group tolerance, giving the terminal
vinylphosphonates in good to excellent isolated yields under mild reaction
conditions.
Y. Fang, L. Zhang, J. Li, X. Jin, M. Yuan, R. Li, R. Wu, J. Fang, Org. Lett.,
2015,
17, 798-801.
[Cp*RhCl2]2 is a very effective catalyst for C-C
coupling of quinones with aryl and alkyl boronic acids under mild conditions. This reaction provides a practical, efficient method
for the synthesis of aryl- and alkylquinones in good yields at room temperature
and under base-free conditions.
D. Wang, B. Ge, L. Du, H. Miao, Y. Ding,
Synlett, 2014, 25, 2895-2898.
A scalable, direct functionalization of various quinones with several boronic
acids proceeds readily at room temperature in an open flask using catalytic
silver(I) nitrate in the presence of a persulfate co-oxidant. The scope with
respect to quinones is broad, with a variety of alkyl- and arylboronic acids
undergoing efficient cross-coupling.
Y. Fujiwara, V. Domingo, I. B. Seiple, R. Gianatassio, M. Del Bel, P. P. S.
Baran, J. Am. Chem. Soc., 2011,
133, 3292-3295.