Michael addition of thiols to alpha,beta-unsaturated carbonyl compounds under solvent-free conditions

A simple and efficient protocol has been introduced for the Michael addition of thiols to alpha, beta-unsaturated carbonyl compounds under solvent-free conditions without the use of a catalyst. The significant features of this reaction are (a) mild reaction conditions, (b) operational simplicity, (c) avoiding toxic and expensive reagents, (d) short reaction times, (e) high product yields, and (f) solvent-free conditions.