Stereoselective Synthesis of <i>Z</i>-α,β-Unsaturated Sulfones Using Peterson Reagents
作者:Kaori Ando、Tomohiro Wada、Miho Okumura、Hiroshi Sumida
DOI:10.1021/acs.orglett.5b03008
日期:2015.12.18
New Peterson reagents were prepared by introducing alkyloxy groups on the silicon atom in order to fix the conformation of the sulfone anion. The reagents 1d and 1e reacted with a variety of aldehydes after the treatment with Li-base to give Z-alpha,beta-unsaturated sulfones with up to >99:1 selectivity in good to excellent yields. For the reaction with aliphatic aldehydes, CPME (cyclopentyl methyl ether) is the choice of solvent, while DME (1,2-dimethoxyethane) gave higher selectivity for the reaction with aromatic aldehydes.