Phenylsilane

Recent Literature

An organotin hydride-catalyzed, silicon hydride-mediated method for effecting the conjugate reduction of α,β-unsaturated ketones was developed.
D. S. Hays, M. Scholl, G. C.Fu, J. Org. Chem., 1996, 61, 6751-6752.

A chemoselective reduction of the carbonyl functionality via hydrosilylation using low loadings of a copper(I) catalyst bearing an abnormal NHC takes place at ambient temperature in excellent yield within a very short reaction time. The hydrosilylation reaction of α,β-unsaturated carbonyl compounds gives allyl alcohols in good yields. The catalyst can also be used for azide-alkyne cycloadditions.
S. R. Roy, S. C. Sau, S. K. Mandal, J. Org. Chem., 2014, 79, 9150-9160.

The combination of triethylborane with an alkali metal base catalyzes the reduction of amides with silanes to form amines under mild conditions. In addition, a selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved.
W. Yao, H. Fang, Q. He, D. Peng, G. Liu, Z. Huang, J. Org. Chem., 2019, 84, 6084-6093.

A well-defined manganese(I) complex with a commercially available bisphosphine ligand catalyzes selective and efficient hydrosilylations of a broad range of esters to alcohols at 100 °C under solvent-free conditions.
R. R. Behera, R. Ghosh, S. Panda, S. Khamari, B. Bagh, Org. Lett., 2020, 22, 3642-3648.

Tetraaryl-1,2,3-triazolium salts are nitrenium-based Lewis acids. These salts catalyze the facile hydrosilylation-deoxygenation of ketones, aldehydes, acetals, alcohols, ethers, and silyl ethers under mild conditions in excellent yields.
D. Ranolia, I. Avigdori, K. Singh, A. Koronatov, N. Fridman, M. Gandelman, Org. Lett., 2022, 24, 3915-3919.

A Ti-catalyzed direct dehydroxylation of tertiary aliphatic alcohols under mild reaction conditions tolerates a wide range of functional groups, including primary alkyl chloride and carbonyl groups. It allows for selective dehydroxylation of tertiary alcohols in diols and the formation of deuterated products with moderate deuterium incorporation.
Q. Lin, W. Tong, X.-Z. Shu, Y. Chen, Org. Lett., 2022, 24, 8459-8464

A simple, mild, metal-free catalytic protocol for an efficient conversion of amides to amines at r.t. uses the stable tetrabutylammonium difluorotriphenylsilicate in combination with silanes that generates a highly reactive hydrosilicate species. The attractive features of this protocol include operational simplicity, safety, broad substrate scope, good yields, and amenable to scale up.
V. Vineyagam, S. K. Sadhukhan, S. K. Karre, R. Srinath, R. K. Maroju, P. R. Karra, H. S. N. B. Bathula, S. Kundrapu, S. R. Surukonti, Org. Lett., 2023, 25, 4610-4614.

A nickel-catalyzed reduction of secondary and tertiary amides provides amines. The reaction transforms various amide substrates, proceeds in the presence of esters and epimerizable stereocenters, and can be used to achieve the reduction of lactams. Moreover, this methodology provides a simple tactic for accessing medicinally relevant α-deuterated amines.
B. J. Simmons, M. Hoffmann, J. Hwang, M. K. Jackl, N. K. Garg, Org. Lett., 2017, 19, 1910-1913.

In a straightforward process for the N-alkylation of amines, readily available carboxylic acids and silanes as the hydride source enable an effective C-N bond construction under mild conditions and allow obtaining a broad range of alkylated secondary and tertiary amines, including fluoroalkyl-substituted anilines as well as the bioactive compound Cinacalcet HCl.
I. Sorribes, K. Jung, M. Beller, J. Am. Chem. Soc., 2014, 136, 14314-14319.

Dibutyltin dichloride catalyzes a direct reductive amination of aldehydes and ketones in the presence of phenylsilane as a stoichiometric reductant. Suitable amines included anilines and dialkylamines but not monoalkylamines.
R. Apodaca, W. Xiao, Org. Lett., 2001, 3, 1745-1748.

A well-defined manganese(II)-NNO pincer complex catalyzes efficient catalytic hydrosilylations of nitroarenes to form the corresponding anilins under solvent-free conditions. This base-metal-catalyzed hydrosilylation is an easy and sustainable alternative to classical hydrogenation. A large variety of nitroarenes bearing various functionalities were selectively reduced in good yields.
R. R. Behera, S. Panda, R. Ghosh, A. A. Kumar, B. Bagh, Org. Lett., 2022, 24, 9179-9183.

A phosphetane-based catalyst operating within P^III/P^V=O redox cycling is able to capture HNO, generated in situ by Nef decomposition of 2-nitropropane, to selectively furnish versatile primary arylamines from arylboronic acid substrates with the preservation of otherwise reactive functional groups.
S. Y. Hong, A. T. Radosevich, J. Am. Chem. Soc., 2022, 144, 8902-8907.

A copper-catalyzed protocol for reductive methylation of amines and imine with formic acid as a C1 source and phenylsilane as a reductant provides the corresponding methylamines in good to excellent yields under mild conditions.
C. Qiao, X.-F. Liu, X. Liu, L.-N. He, Org. Lett., 2017, 19, 1490-1493.

Co₂(CO)₈ catalyzes chemodivergent syntheses of pyrrolidines and pyrrolidones from levulinic acid and aromatic amines under slightly different hydrosilylation conditions. 1.5 and 3 equiv of phenylsilane selectively yielded pyrrolidone and pyrrolidine, respectively.
S. Panda, A. Nanda, R. Saha, R. Ghosh, B. Bagh, J. Org. Chem., 2023, 88, 16997-17009.

A Cu-catalyzed reductive aminocarbonylation of primary, secondary, and tertiary alkyl iodides using nitroarenes as the nitrogen source provides a diverse range of secondary N-aryl alkylamides. The single copper catalyst synergistically mediates both carbonylation of alkyl iodides and reduction of nitroarenes, to provide acyl iodides and anilines as possible reactive intermediates.
S. Zhao, N. P. Mankad, Org. Lett., 2019, 21, 10106-10110.

A nickel-catalyzed N-N cross-coupling of O-benzoylated hydroxamates with a broad range of aryl and aliphatic amines provides hydrazides in an up to 81% yield. Experimental evidence implicates the intermediacy of electrophilic Ni-stabilized acyl nitrenoids and the formation of a Ni(I) catalyst via silane-mediated reduction.
J. P. Barbor, V. N. Nair, K. R. Sharp, T. D. Lohrey, S. E. Dibrell, T. K. Shah, M. J. Walsh, S. E. Reisman, B. M. Stoltz, J. Am. Chem. Soc., 2023, 145, 15071-15077.

A new strategy for the catalytic asymmetric aldol reaction of ketones was developed that relies on a chiral copper(I) complex-catalyzed domino reduction/aldol reaction sequence in the presence of phenylsilane.
J. Deschamp, O. Chuzel, J. Hannedouche, O. Riant, Angew. Chem. Int. Ed., 2006, 45, 1292-1297.

The sequential combination of Ti-catalyzed hydroamination of alkynes followed by the Ti-catalyzed hydrosilylation of the intermediate imines is an efficient one-pot process for the conversion of alkynes and primary amines into secondary amines.
A. Heutling, F. Pohlki, I. Bytschkov, S. Doye, Angew. Chem. Int. Ed., 2005, 44, 2951-2954.

An indium triiodide catalyzed deoxygenative functionalization of N-sulfonyl amides with silyl cyanide or silyl enolates in the presence of hydrosilanes gives α-cyanoamines and β-aminocarboxyl compounds, respectively.
Y. Inamoto, Y. Kaga, Y. Nishimoto, M. Yasuda, A. Baba, Org. Lett., 2013, 15, 3448-3451.

Y. Inamoto, Y. Kaga, Y. Nishimoto, M. Yasuda, A. Baba, Org. Lett., 2013, 15, 3448-3451.

The In(OAc)₃-catalyzed reaction of bromo- and iodoalkanes with PhSiH₃ in THF at 70 C gave dehalogenated alkanes in good to high yields in the presence of Et₃B and air. 2,6-lutidine as additive enabled an efficient reduction of simple and functionalized iodoalkanes in EtOH. GaCl₃ was found to be an effective catalyst for the reduction of haloalkanes with poly(methylhydrosiloxane).
K. Miura, M. Tomita, Y. Yamada, A. Hosomi, J. Org. Chem., 2007, 72, 787-792.

B(C₆F₅)₃ catalyzes dehydrogenative couplings of certain amines and hydrosilanes at elevated temperatures. At higher temperature, the dehydrogenation pathway competes with cleavage of the C-N bond and defunctionalization is obtained. This can be turned into a useful methodology for the transition-metal-free reductive deamination of a broad range of amines.
H. Fang, M. Oestreich, Angew. Chem. Int. Ed., 2020, 59, 11394-11398.

An iron(III)-promoted hydroalkynylation of unactivated mono-, di-, and trisubstituted alkenes provides structural diversified alkynes via Csp-Csp³ bond formation.
Y. Shen, B. Huang, J. Zheng, C. Lin, Y. Liu, S. Cui, Org. Lett., 2017, 19, 1744-1747.

A route to trisubstituted olefins through a palladium-catalyzed alkyne insertion with unactivated alkyl iodides followed by a reduction proceeds under mild conditions and tolerates a range of functional groups and substitution patterns. Mechanistic inquiry suggests that the transformation proceeds through a hybrid radical/organometallic pathway.
E. R. Fruchey, B. M. Monks, A. M. Patterson, S. P. Cook, Org. Lett., 2013, 15, 4362-4365.

Catalytic enone hydrometallation represents a promising strategy for enolate generation, circumventing the utilization of preformed enol or enolate derivatives. Metal-catalyzed reductive condensation of α,β-unsaturated carbonyl compounds with aldehydes in the presence of a hydride donor enable highly diastereoselective aldol and Michael cycloreductions.
T.-G. Baik, A. L. Luis, L.-C. Wang, M. J. Krische, J. Am. Chem. Soc., 2001, 123, 5112-5113.

A highly Marknovikov selectiv conversion of various olefins to azides was achieved using a cobalt catalyst, 3 equiv of TsN₃ as nitrogen source and simple silanes (PhSiH₃, TMDSO).
J. Waser, H. Nambu, E. M. Carreira, J. Am. Chem. Soc., 2005, 127, 8294-8295.

A convenient protocol for the catalytic dehydration of aromatic and aliphatic amides using silanes in the presence of catalytic amounts of fluoride allows the synthesis of a wide range of aliphatic and aromatic nitriles with high selectivity under mild conditions.
S. Zhou, K. Junge, D. Addis, S. Das, M. Beller, Org. Lett., 2009, 11, 2461-2464.

In a catalytic system for the chlorination of alcohols under Appel conditions, benzotrichloride is used as a cheap and readily available chlorinating agent in combination with trioctylphosphane as the catalyst and phenylsilane as the terminal reductant under solvent-free conditions. In total, 27 different primary, secondary, and tertiary alkyl chlorides were synthesized in good yields.
L. Longwitz, S. Jopp, T. Werner, J. Org. Chem., 2019, 84, 7863-7870.

The combination of Pd(PCy₃)₂Cl₂ and di-2-pyridyl ketone catalyzes a reductive formylation of aryl iodides with carbon dioxide as the carbonyl source under mild reaction conditions in the presence of phenylsilane as the reductive reagent. This convenient reaction provides a variety of aromatic aldehydes in good yields with wide substrate scope and good functional group tolerance.
D. Li, L. Wei, W. Xiong, H. Jiang, C. Qi, J. Org. Chem., 2023, 88, 5231-5237.

An organophosphorus-catalyzed reductive C-N coupling of nitromethane with arylboronic acid derivatives provides N-methylanilines. The small ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) together with phenylsilane as mild terminal reductant mediate the selective installation of the methylamino group.
G. Li, Z. Qin, A. T. Radosevich, J. Am. Chem. Soc., 2020, 142, 16205-16210.

A mild transition-metal- and photosensitizer-free photoredox system based on the combination of NaI and PPh₃ enables a highly selective reduction of nitroarenes. This protocol tolerates a broad range of reducible functional groups such as halogen (even I), aldehyde, ketone, carboxyl, and cyano.
Z. Qu, X. Chen, S. Zhong, G.-J. Deng, H. Huang, Org. Lett., 2021, 23, 5349-5353.

A transition-metal-free synthesis of aryl- and heteroarylamines employs a small-ring organophosphorus-based catalyst and a terminal hydrosilane reductant to drive reductive intermolecular coupling of nitroarenes with boronic acids. Applications to the construction of both C_sp2-N (from arylboronic acids) and C_sp3-N bonds (from alkylboronic acids) are demonstrated; the reaction is stereospecific with respect to C_sp3-N bond formation.
T. V. Nykaza, J. C. Cooper, G. Li, N. Mahieu, A. Ramirez, M. R. Luzung, A. T. Radosevich, J. Am. Chem. Soc., 2018, 140, 15200-15205.

A Fe-catalyzed olefin hydroamination with aryldiazo sulfones provides a broad range of alkylarylazo compounds, that are difficult to access. The reaction offers mild reaction conditions.
Y. Zhang, C. Huang, X. Lin, Q. Hu, B. Hu, Y. Zhou, G. Zhu, Org. Lett., 2019, 21, 2261-2264.

An organophosphorus-catalyzed umpolung reaction achieves the deoxygenation of sulfonyl chlorides and alcohols/acids to synthesize thioethers/thioesters driven by P^III/P^V=O redox cycling. This operationally simple approach uses a stable phosphine oxide as a precatalyst and shows broad functional group tolerance.
G. Sun, J. Li, X. Liu, Y. Liu, X. Wen, H. Sun, Q.-L. Xu, J. Org. Chem., 2023, 88, 8628-8635.

P^III/P^V=O redox cycling enables a one-step dehydroxylative thioetherification of alcohols with various hypervalent organosulfur compounds. This method offers excellent functional group tolerance, broad substrate scope, and scalability.
G. Sun, S.-P. Zhang, Y.-F. Zhao, Y. Du, M.-Y. Shi, J. Li, H. Yuan, X. Wen, H. Sun, Q.-L. Xu, J. Org. Chem., 2024, 89, 1083-1090.

1,2,2,3,4,4-hexamethylphosphetane catalyzes a deoxygenative N-N bond-forming Cadogan heterocyclization of o-nitrobenzaldimines and o-nitroazobenzenes with good functional group compatibility in the presence of phenylsilane as terminal reductant.
T. V. Nykaza, T. S. Harrison, A. Ghosh, R. A. Putnik, A. T. Radosevich, J. Am. Chem. Soc., 2017, 139, 6839-6842.

Catalytic amounts of phosphine and triethylamine enable an efficient protocol for the synthesis of highly functionalized furans via intramolecular Wittig reaction. Silyl chloride as the initial promoter activates the phosphine oxide for reduction, while decomposition of Et₃N·HCl resulted in regeneration of base, which mediated formation of phosphorus ylide.
C.-J. Lee, T.-H. Chang, J. K. Yu, G. M. Reddy, M.-Y. Hsiao, W. Lin, Org. Lett., 2016, 18, 3758-3761.

A chiral phosphine oxide catalyzes an asymmetric Staudinger-aza-Wittig reaction of (o-azidoaryl)malonates to provide chiral quaternary oxindoles in the presence of a silane reductant and an Ir^I-based Lewis acid. The reaction occurs under mild conditions, with good functional group tolerance, a wide substrate scope, and excellent enantioselectivity.
C. Xie, J. Kim, B. K. Mai, S. Cao, R. Ye, X.-Y. Wang, P. Liu, O. Kwon, J. Am. Chem. Soc., 2022, 144, 21318-21327.

An efficient regio- and chemoselective dearomatization of a wide range of N-heteroarenes using hydrido-cobalt catalysts can be performed under mild conditions. Various quinolines and pyridines bearing electron-donating and electron-withdrawing substituents are compatible with this methodology.
C. C. Bories, G. Gontard, M. Barbazanges, E. Derat, M. Petit, Org. Lett., 2023, 25, 843-848.