α,β-unsaturated (S)-cyanohydrins derived from 2-propenal, 2-butenal, (E) and (Z)-2-hexenal and 2-hexynal are obtained in high enantiomeric purity (80–95% e.e.) by using an oxynitrilase isolated from the leaves of Hevea brasiliensis.
A Facile Synthesis of Optically Active γ-Cyanoallylic Alcohols Using Asymmetric Hydrocyanation of α,β-Alkenyl Aldehydes Followed by Stereospecific [3.3]Sigmatropic Chirality Transfer of the Cyanohydrin Acetates
Optically active γ-cyanoallylic alcohols were synthesized by using asymmetric hydrocyanation of α,β-alkenyl aldehydes catalyzed by peptide-titanium complex to give α-cyanoallylic alcohols (cyanohydrins) with high optical yields followed by palladium complex catalyzed [3.3]sigmatropic chirality transfer of the corresponding acetates.
PmHNL catalyzed synthesis of (R)-cyanohydrins derived from aliphatic aldehydes
作者:Samik Nanda、Yasuo Kato、Yasuhisa Asano
DOI:10.1016/j.tetasy.2006.02.003
日期:2006.3
Hydroxynitrile lyase from the Japanese apricot (Prunus mume) catalyzes the formation of several aliphatic cyanohydrins in an asymmetric fashion. By employing a biphasic reaction system, aliphatic aldehydes with various structural features can be converted to the corresponding (R)-cyanohydrins with good overall yield and enantiomeric excess. (c) 2006 Elsevier Ltd. All rights reserved.
Study on the (R)-oxynitrilase activity of Pouteria sapota
作者:Aida Solís、Héctor Luna、Norberto Manjarrez、Herminia I. Pérez
DOI:10.1016/j.tet.2004.07.102
日期:2004.11
Mamey (Pouteria sapota) defatted meal was used to catalyze the enantioselective addition of HCN to alpha, beta-unsaturated aldehydes. Using a biphasic system of diisopropyl ether and citrate buffer (0.1 M, pH 5.0, 10% v/v), the (R)-cyanohydrins obtained showed good conversion (from 54 to 98%) and enantiomeric excess (from 74 to 99%). (C) 2004 Elsevier Ltd. All rights reserved.