Enantioselective Preparation of ω-Functionalized O-Acylated Cyanohydrins

• Main Author: Heid, Berenice
• Format: Others
• Language: English
• Published: KTH, Skolan för kemivetenskap (CHE) 2011
• Subjects: metal catalyst; enzyme; chiral; cyanohydrin; minor enentiomer recycling
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-40896

A minor enantiomer recycling one-pot process usingω-functionalized prochiral aldehydes as starting materials and two reinforcing catalysts has been reported. The desired aldehyde for these process studies was 5-bromo-1-pentanal. In a two-phase solvent system, enzyme-catalyzed hydrolysis of the minor enantiomer regenerates continuously the prochiral starting material and Lewis acid catalysed addition of acetyl cyanide provides the O-acetylated cyanohydrins. The minor enantiomer recycling process has been studied and improved for 5-bromo-1-pentanal to receive high enantiomeric excess and yield of the expected O-acetylated cyanohydrin.