On the reaction of thioacetals with sulphuryl chloride

Abstract

Sulphuryl chloride reacts with 1,3-oxathiolans and 1,3-dithiolans to afford unstable intermediate trans-2,3-dichloro-1,4-oxathians or trans-2,3-dichloro-1,4-dithians. Some of these intermediates can be converted on hydrolytic work up to α-ketothioacetals in reasonable yield. Intermediates in the rearrangement pathway have been identified. Reaction of 6-oxospiro[cyclohexane-1,2′-1′,3′-oxathiolan](4) with toluene-p-sulphonic acid gave 2,14-dioxa-11-thiatetracyclo[7.5.3.0^1,10.0^3,8]heptadec-3-en-4-one (20), a novel tetracyclic compound whose structure was determined by X-ray crystallography.