Three chiral beta-hydroxy amide ligands were prepared by the reaction of benzyl chloride with amino alcohols derived from L-tyrosine. The titanium(IV) complex of chiral ligand 4a was found to be an effective catalyst for the asymmetric addition of methyl propiolate, to aliphatic and aromatic aldehydes. The gamma-hydroxy-alpha,beta-acetylenic esters were obtained in excellent enantiomeric excesses (up to 94% ee) under optimized conditions. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.
A General Asymmetric Synthesis of (R)-Matsutakeol and Flavored Analogs
作者:Jia Liu、Honglian Li、Chao Zheng、Shichao Lu、Xianru Guo、Xinming Yin、Risong Na、Bin Yu、Min Wang
DOI:10.3390/molecules22030364
日期:——
and practical syntheticroute toward chiral matsutakeol and analogs was developed by asymmetric addition of terminal alkyne to aldehydes. (R)-matsutakeol and other flavored substances were feasibly synthesized from various alkylaldehydes in high yield (up to 49.5%, in three steps) and excellent enantiomeric excess (up to >99%). The protocols may serve as an alternative asymmetric synthetic method for