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Reaction of aryl and styryl methyl ketones 1a‐m with dimethyl bis(methylthio)methylenemalonate (2) in the presence of potassium hydroxide in dimethyl sulfoxide gave the corresponding methyl 6‐aryl‐ and 6‐styryl‐4‐methylthio‐2‐oxo‐2H‐pyran‐3‐carboxylates 3a‐m.6‐Aryl derivatives 3a‐d,g were treated with sodium methoxide in methanol to give the corresponding 6‐aryl‐4‐methoxy‐2H‐pyran‐2‐ones 8a‐d and 9. Phenylcoumalin (7a) and paracotoin (7b) were synthesized by the desulfurization of 6‐aryl‐4‐methylthio‐2H‐pyran‐2‐ones 4a,b. Similarly, anibine (8e) was also synthesized from 3g.Treatment of 3 with hydrogen peroxide or 3‐chloroperoxybenzoic acid gave the corresponding 4‐methylsulfiny‐2H‐pyran‐2‐ones 10a‐f in good yields. Displacement reactions of 10a‐f with nucleophilic reagents are also described.

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