Trifluoromethane sulphonic acid: a Brönsted acid catalyst for the addition of allyltributylstannanes to carbonyl compounds in water
作者:Teck-Peng Loh、Jia Xu
DOI:10.1016/s0040-4039(99)00122-7
日期:1999.3
Trifluoromethane sulphonic acid catalyses the addition of allyltributylstannane to carbonyl compounds in water to give the corresponding homoallylic alcohols in high yields.
Enantioselective synthesis of unsaturated α-hydroxy acids
作者:Jacqueline A. Macritchie、Alan Silcock、Christine L. Willis
DOI:10.1016/s0957-4166(97)00571-5
日期:1997.12
(S)- and (R)-2-Hydroxyhex-5-enoic acid and (S)- and (R)-2-hydroxyhept-6-enoic acid were prepared in excellent yields and enantiomeric excesses (>99% ee) from the corresponding α-keto esters by the enzyme catalysed hydrolysis of the ester and reduction of the ketone in a single pot process. The enantioselectivesynthesis of (S)-2-hydroxypent-4-enoic acid was achieved via reaction of the reagent derived
Diastereoselective allylation of N-glyoxyloyl-(2R)-bornane-10,2-sultam and (1R)-8-phenylmenthyl glyoxylate: synthesis of (2S,4S)-2-hydroxy-4-hydroxymethyl-4-butanolide
The diastereoselective addition of allylsilanes and allylstannanes to N-glyoxyloyl-(2R)-bornane-10,2-sultam 1 and (1R)-8-phenylmenthyl glyoxylate 7 in the presence of Lewis acids has been studied. We obtained diastereoselectivities up to 84% and 94% for the allylation of 2 and 7, respectively. The application of the allylation products of 1 or 2 in the synthesis of 4-butanolides, for example (2S,4S)-2-hydroxy-4-hydroxymethyl-4-butanolide 13 is presented. (C) 2004 Elsevier Ltd. All rights reserved.