An Asymmetric Ortholithiation Approach to Inherently Chiral Calix[4]arenes
作者:Simon A. Herbert、Gareth E. Arnott
DOI:10.1021/ol902238p
日期:2009.11.5
A general asymmetric synthesis of inherentlychiralcalix[4]arenes is described: using a chiral oxazoline derived from l-valine, an ortholithiation strategy is employed to give inherentlychiralcalix[4]arenes with high (93%) enantiomeric excesses. A crystal structure of a phosphine oxide intermediate has been obtained, unambiguously assigning the major diastereomer in the reaction; a mechanism explaining