Selective Synthesis of α,β-Unsaturated Ketones by Dibutyltin Dimethoxide-Catalyzed Condensation of Aldehydes with Alkenyl Trichloroacetates

Various α,β-unsaturated ketones were stereoselectively synthesized in high yields up to 94% by a condensation reaction between alkenyl trichloroacetates and aldehydes using dibutyltin dimethoxide as a catalyst in the presence of methanol. This process is superior to the classical Claisen−Schmidt condensation with respect to mildness of the base catalyst and product selectivity