A New Synthesis of 3-Aryl-5-Arylmethylene-2(5H)-Furanones

A recent report about the synthesis of di and tri-substituted 2 (5H)-furanones starting from bromoaldehydes and potassium phenyl-acetate¹ prompts us to report our own studies on the preparation of 3-aryl-5-arylmethylene-2 (5H)-furanones (or butenolides) 1. We have earlier reported² a general method for the synthesis of 1 from phenylpropargyl aldehyde, 2 and arylacetic acids. Although several methods have been reported for the synthesis of the parent compound 1 (R = R₁ = Ph)^3–6, these methods have not been extended to other substituted furanones. Saikachi and Taniguchi⁷ prepared 1 (R = 5-nitro-2-thenyl, R₁ = 2-thenyl and 2-furyl) in 16–17% yields.