Enantioselective Oxetane Ring Opening with Chloride: Unusual Use of Wet Molecular Sieves for the Controlled Release of HCl
作者:Wen Yang、Zhaobin Wang、Jianwei Sun
DOI:10.1002/anie.201601844
日期:2016.6.6
An unprecedented enantioselectiveoxetaneopening with chloride provides access to a range of highly functionalized three‐carbon building blocks. The excellent enantiocontrol is enabled not only by a new catalyst, but also by the unusualuse of wetmolecularsieves for the controlledrelease of HCl.
The enantioselectivity of the lipase from Pseudomonas cepacia (PCL) in the transesterification of 2-phenyl-1-propanol I was studied using a series of vinyl 3-arylpropanoates as acyl donors. The most enantioselective transesterification reaction of the alcohol was attained by using vinyl 3-(p-iodophenyl)- or 3-(p-trifluoromethylphenyl)propanoates, with enantiomer ratios, E, of 116 and 138, respectively. Vinyl 3-phenylpropanoate was also effective for the resolution of 1 mediated by lipases from P. fluorescens and porcine pancreas and for the PCL-catalysed transesterification of several 2-phenyl-1-alkanols. The enantiomeric resolution of 1 was practically carried out by the first enantioselective transesterification using PCL and vinyl 3-(p-iodophenyl)propanoate to afford (R)-1 and then the enantioselective hydrolysis of the resultant ester to afford (S)-1. (C) 2001 Elsevier Science Ltd. All rights reserved.