Baylis–Hillman Reaction Assisted by aliquat-336 and triphenylphosphine Under Ultrasound Radiation

Abstract

The activation of Baylis–Hillman reaction by aliquat-336 and triphenylphosphine under ultrasound radiation is described. A significant improvement of the yield of Baylis–Hillman reaction was observed. We illustrate the effects of the solvent, the nature of the nucleophilic agent, the phase transfer catalyst and ultrasound, on the Baylis–Hillman reaction efficiency. The reaction examined involves methyl acrylate, which, in the presence of nucleophilic agent, forms a zwitterionic intermediate, which reacts with the aldehyde to subsequently give the product of the reaction. For all the aldehydes tested, it was found that ultrasound radiation in the presence of aliquat-336 could reduce the duration of the Baylis–Hillman reaction and improve the reaction efficiency. This method could be a clean, economical, efficient and safe technology in organic synthesis to prepare Baylis–Hillman adducts.