Chemistry of 1,4-Dioxene; IV1. A General Method for the Preparation of 2-Oxoalkanal 1-Dithioacetals from Ketones

Abstract

The tertiary allylic alcohols obtained from lithiated dihydro-1,4-dioxin and ketones, 2-(1-hydroxyalkyl)-5,6-dihydro-1,4-dioxins, react with 1,2-ethanedithiol and 1,3-propanedithiol in dichloromethane in the presence of catalytic amounts of ether-boron trifluoride to give, after acid hydrolysis, 2-acyl-1,3-dithiolanes or 2-acyl-1,3-dithianes, respectively, i.e., 2-oxoalkanal 1-dithioacetals.