Ruthenium- and lipase-catalyzed DYKAT of 1,2-diols: an enantioselective synthesis of syn-1,2-diacetates
摘要:
Regio- and stercoselective lipase-catalyzed kinetic resolutions were investigated for some unsymmetrical, secondary/secondary syn-diols. Candida antarctica lipase B-catalyzed transesterifications of a few aryl/alkyl- and alkyl/alkyl 1,2-diols were coupled in one-pot for efficient ruthenium-catalyzed epimerization and intramolecular acyl migration to give a dynamic kinetic asymmetric transformation (DYKAT) affording enantioenriched (ee up to > 99%) syn-diacetates as the main diastereomers (sywanti similar to 2:1 to 10:1). (c) 2006 Elsevier Ltd. All rights reserved.
Diastereoselectivity in the Reduction of α-Oxy- and α-Amino-Substituted Acyclic Ketones by Polymethylhydrosiloxane
作者:Durgesh Nadkarni、James Hallissey、Carlos Mojica
DOI:10.1021/jo0260544
日期:2003.1.1
Diastereoselectivity in the reduction of alpha-alkoxy-, alpha-acyloxy-, and alpha-alkylamino-substituted ketones with polymethylhydrosiloxane (PMHS) in the presence of fluoride ion catalysis was investigated. High syn-selectivity was observed in the reduction of alpha-alkoxy, alpha-acyloxy, and alpha-dialkylamino ketones. Reduction of alpha-monoalkylamino ketone proceeded in anti-selective manner with