Triethylsilane (TES)
Recent Literature
An Et3SiH-promoted diastereoselective reductive aldol
reaction has been developed using InBr3 as a catalyst. This
three-component reaction afforded only silyl aldolates as products
without any side reactions.
I. Shibata, H. Kato, T. Ishida, M. Yasuda, A. Baba, Angew. Chem. Int. Ed.,
2004,
43, 711-714.
An efficient methodology for the reductive alkylation of secondary amines
with aldehydes and Et3SiH using an iridium complex as a catalyst
has been developed. In addition, a cheaper, easy-to-handle, and
environmentally friendly reducing reagent such as polymethylhydrosiloxane
(PMHS) in place of Et3SiH was also useful.
T. Mizuta, S. Sakaguchi, Y. Ishii, J. Org. Chem., 2005, 70, 2195-2199.
Reductive amination of aldehydes and ketones with the InCl3/Et3SiH/MeOH
system is highly chemoselective and can be applied to various cyclic, acyclic,
aromatic, and aliphatic amines. Functionalities including ester, hydroxyl,
carboxylic acid, and olefin are tolerated.
O.-Y. Lee, K.-L. Law, C.-Y. Ho, D. Yang, J. Org. Chem., 2008,
73, 8829-8837.
Facile reductive etherification of carbonyl compounds can be conveniently
performed by reaction with triethylsilane and alkoxytrimethylsilane
catalyzed by iron(III) chloride. The corresponding alkyl ethers, including
benzyl and allyl ethers, of the reduced alcohols were obtained in good to
excellent yields under mild reaction conditions.
K. Iwanami, H. Seo, Y. Tobita, T. Oriyama, Synthesis, 2005, 183-186.
A novel one-pot procedure for a directly reductive conversion of esters to the
corresponding ethers by Et3SiH in the presence of a catalytic amount
of InBr3 is described. This simple catalytic system appeared to be
remarkably tolerant to several functional groups.
N. Sakai, T. Moriya, T. Konakahara, J. Org. Chem., 2007,
72, 5920-5922.
Various silyl ethers were readily and efficiently transformed into the
corresponding alkyl ethers in high yields by the use of aldehydes combined with
triethylsilane in the presence of a catalytic amount of iron(III) chloride.
K. Iwanami, K. Yano, T. Oriyama, Synthesis, 2005, 2669-2672.
A chemoselective activation of a secondary amide with triflic anhydride in the
presence of 2-fluoropyridine enables a mild reduction using triethylsilane, a
cheap and rather inert reagent. Imines can be isolated after a basic workup or
readily transformed to the aldehydes following an acidic workup. The amine
moiety can be accessed by addition of Hantzsch ester to the reaction mixture.
G. Pelletier, W. S. Bechara, A. B. Charette, J. Am. Chem. Soc., 2010,
132, 12817-12819.
A palladium-catalyzed reduction of 2-pyridinyl esters using hydrosilanes is
applicable to the preparation of aliphatic, aromatic, and α,β-unsaturated
aldehydes. Various functional groups, such as fluoro, methoxy, aldehyde, acetal,
and ester, are tolerated.
J. Nakanishi, H. Tatamidani, Y. Fukumoto, N. Chatani, Synlett,
2006, 869-872.
Optimizations to generate CuH in situ have led to an efficient and
inexpensive hydrosilylation method for dialkyl ketones.
B. H. Lipshutz, C. C. Caires, P. Kuipers, W. Chrisman, Org. Lett., 2003, 5, 3085-3088.
A regioselective reductive ring opening of benzylidene acetals in carbohydrate
derivatives using triethylsilane and molecular iodine is fast and compatible
with most of the functional groups encountered in oligosaccharide synthesis, and
offers excellent yields. The reaction conditions are equally effective in
thioglycosides.
R. Panchadhayee, A. K. Misra, Synlett, 2010,
1193-1196.
Aliphatic carboxyl derivatives (acids, acyl chlorides, esters) and
aldehydes were efficiently reduced to the methyl group by HSiEt3
in the presence of catalytic amounts of B(C6F5)3.
Aromatic carboxylic acids, as well as other carbonyl functional
equivalents, underwent smooth partial reduction to the corresponding
TES-protected benzylic alcohols in competition with a
Friedel-Crafts-like alkylation decreasing the overall selectivity of
the reduction process.
V. Gevorgyan, M. Rubin, J.-X. Liu, Y. Yamamoto, J. Org. Chem, 2000, 66, 1672-1675.
V. Gevorgyan, M. Rubin, J.-X. Liu, Y. Yamamoto, J. Org. Chem, 2000, 66, 1672-1675.
In situ generation of molecular hydrogen by addition of triethylsilane to
palladium on charcoal results in rapid and efficient reduction of multiple bonds,
azides, imines, and nitro groups, as well as deprotection of benzyl and allyl
groups under mild, neutral conditions.
P. K. Mandal, J. S. McMurray, J. Org. Chem.,
2007,
72, 6599-6601.
A new procedure for catalytic reductive coupling of aldehydes and alkynes
uses Ni(COD)2 with an imidazolium carbene ligand as the catalyst and
triethylsilane as the reducing agent.
G. M. Mahandru, G. Liu, J. Montgomery, J. Am. Chem. Soc., 2004, 126, 3698-3699.
A three-component nickel-catalyzed coupling of enals, alkynes, and silanes forms
an enol silane and a trisubstituted alkene with >98:2 stereoselectivity. The
reaction tolerates a broad range of functionality including aldehydes, ketones,
esters, free hydroxyls, and basic secondary amines.
A. Herath, J. Montgomery, J. Am. Chem. Soc., 2008,
130, 8132-8133.
The use of a catalytic amount of PtCl2 enables the conversion of
α-hydroxypropargylsilanes to (Z)-silylenones through a highly selective
silicon migration via alkyne activation. The complementary (E)-silylenones are
accessed by a regioselective hydrosilylation of the ynone precursor.
D. A. Rooke, E. M. Ferreira, J. Am. Chem. Soc., 2010,
132, 11926-11928.
Indium hydride (Cl2InH) was generated by the transmetalation of InCl3
with Et3SiH. In the previously reported system (NaBH4-InCl3), the coexistent borane can
cause side reactions. The use of Et3SiH instead of NaBH4 affords effective hydroindation of alkynes.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.
Palladium-catalyzed reduction of aromatic nitro groups to amines can be
accomplished in high yield, with wide functional group tolerance and short
reaction times at r.t. using aqueous potassium fluoride and
polymethylhydrosiloxane (PMHS) for aromatic nitro groups. Aliphatic nitro
compounds are reduced to the corresponding hydroxylamines using
triethylsilane instead of PMHS/KF.
R. J. Rahaim, R. E. Maleczka (Jr.), Org. Lett., 2005, 7, 5087-5090.
Organic azides are easily and chemoselectively reduced to the corresponding amines by reaction
with dichloroindium hydride under very mild conditions. γ-Azidonitriles
give pyrrolidin-2-imines in an outstanding
cyclization.
L. Benati, G. Bencivenni, R. Leardini, D. Nanni, M. Minozzi, P. Spagnolo, R.
Scialpi, G. Zanardi, Org. Lett., 2006, 8, 2499-2502.
L. Benati, G. Bencivenni, R. Leardini, D. Nanni, M. Minozzi, P. Spagnolo, R.
Scialpi, G. Zanardi, Org. Lett.,
2006,
8, 2499-2502.
Reduction of ethanethiol esters of α-amino acids to α-amino aldehydes by
triethylsilane and catalytic palladium-on-carbon is described. α-Amino aldehydes
with Boc, Cbz, or Fmoc protection could be obtained without racemization in high
yield.
H. Tokuyama, S. Yokoshima, S.-C. Lin, L. Li, T. Fukuyama, Synthesis,
2002, 1121-1123.
H. Tokuyama, S. Yokoshima, T. Yamashita, S.-C. Lin, L. Li, T. Fukuyama,
J. Braz. Chem. Soc., 1998, 9, 381-387.
