Structure and some reactions of dimethyloxosulphonio-(3-oxocyclohex-1-enyl)methanide

Abstract

Stable crystalline dimethyloxosulphonio-(3-oxocyclohex-1-enyl)methanide (I) was prepared from 3-chloro-cyclohex-2-enone by reaction with dimethyloxosulphoniomethanide. Acylation and alkylation of (I) provided convenient routes to 3-acetonylcyclohex-2-enone (VI), 3-phenacylcyclohex-2-enone (VII), 3-acetyl-2-methyl-5-(3-oxocyclohex-1-enyl)furan (IX), and 3-(1-iodoethyl)cyclohex-2-enone (X). The structure of the ylide (I) is discussed.