THE REACTION OF CHLOROSULFONIC ACID WITH BENZALACETONE AND BENZALPINACOLONE

Freshly prepared benzalacetone (1) can be converted into styrene-4, β-disulfonyl dichloride (3) on treatment with an excess of chlorosulfonic acid. The yield is influenced by the work-up conditions. A number of derivatives have been prepared from 3, by reaction with nitrogen nucleophiles. Benzalpinacolone (5), which precludes enolisation-a key step in the conversion of 1 into 3, was also converted into 3 on treatment with an excess of chlorosulfonic acid. The identity of the product was confirmed by reaction with dimethylamine and morpholine, which gave the bis-sulphonamides (4) and (16) respectively. A reaction mechanism for the conversion of (5) into (3) has been proposed. © 1990, Taylor & Francis Group, LLC. All rights reserved.