A facile and enantioselective method for the multigram preparation of the title compounds is described. The Michael addition of thiophenols to chalcones catalyzed by (+)-cinchonine, followed by crystallization, led to the corresponding adducts 2 in up to > 95% e.e. The stereoselective Beckmann rearrangement of the oxime of (+)-1,3-diphenyl-3-phenylsulfanylpropan-1-one 2a gives the anilide of (R)-(+)-3-phenyl-3-phenylsulfanylpropanoic acid (as determined by X-ray analysis) and alcoholysis leads to the corresponding enantiomerically pure ethyl ester. (C) 2001 Elsevier Science Ltd. All rights reserved.
Diastereoselective Thiophenol Addition to (S)-N-.alpha.,.beta.-Unsaturated carbonyl- .gamma.-[(trityloxy)methyl]-.gamma.-butyrolactams
作者:Kiyoshi Tomioka、Aki Muraoka、Motomu Kanai
DOI:10.1021/jo00124a039
日期:1995.9
Rh-Catalyzed Asymmetric Hydrogenation of β-Substituted-β-thio-α,β-unsaturated Esters: Expeditious Access to Chiral Organic Sulfides
作者:Gang Liu、Zhengyu Han、Xiu-Qin Dong、Xumu Zhang
DOI:10.1021/acs.orglett.8b02339
日期:2018.9.21
Rh/bifunctional bisphosphine-thiourea ligand (ZhaoPhos)-catalyzed asymmetric hydorgenation of both (Z)- and (E)-isomers of β-substituted-β-thio-α,β-unsaturated esters was successfully developed. This new asymmetric catalytic methodology provided highly efficient access to two enantiomers of chiral organic sulfides ethyl β-substituted-β-thio-propanoates with excellent results (up to 99% yield and >99%
Chiral Amino Ether-Controlled Catalytic Enantioselective Arylthiol Conjugate Additions to α,β-Unsaturated Esters and Ketones: Scope, Structural Requirements, and Mechanistic Implications
作者:Katsumi Nishimura、Kiyoshi Tomioka
DOI:10.1021/jo015879v
日期:2002.1.1
Asymmetric conjugate addition reaction of 2-trimethylsilylbenzenethiol with enoates and enones is catalyzed by a chiral amino ether-lithium thiolate complex and affords adducts with high enantioselectivity. Both the s-cis conformation and a steric wall at one side of the carbonyl group are structural requirements in substrates yielding adducts with high enantioselectivity. Reactions with tert-butyl