Phosphonium ionic liquids-accelerated Morita-Baylis-Hillman reaction

Abstract

Phosphonium ionic liquids, due to their superior thermal stability and an inertness in weak basic reaction media, are receiving more and more attention. A series of phosphonium ionic liquids have been prepared starting from cheap tributylphosphine with various halogenated hydrocarbon. Then using 1,4-diazabicyclo[2.2.2]octane (DABCO) as catalyst and water-phosphonium ionic liquid composite system as reaction media, Morita-Baylis-Hillman reactions of a variety of aldehydes with acrylonitrile, methyl acrylate or acrylamide were studied. Experimental results showed that the composite system of phosphonium ionic liquid with water can effectivily accelerate the Morita-Baylis-Hillman reactions of aromatic aldehydes and aliphatic aldehydes, and fast reaction rate and high yield were obtained.