Highly diastereoselective [2+2] cycloadditions via chelation control: Asymmetric synthesis of β-lactones
作者:Ronald Zemribo、Daniel Romo
DOI:10.1016/0040-4039(95)00716-p
日期:1995.6
Chelation controlled [2+2] cycloadditions of trimethylsilylketene to chiral alpha- and beta-benzyloxyaldehydes followed by desilylation provides a highly diastereoselective route to functionalized beta-lactones. Several Lewis acids were examined and MgBr2 . Et(2)O was found to give the highest diastereoselectivities and yields.