Mannich‐Type Reaction Using Alkenyl Trichloroacetates Catalyzed by Dibutyltin Dimethoxide

A novel Mannich‐type reaction of alkenyl trichloroacetates with aldimines has been realized by using dibutyltin dimethoxide as a catalyst, which is regenerated by addition of methanol. A three‐component coupling reaction of aldehydes, primary amines, and alkenyl trichloroacetates has been also efficiently achieved. These procedures can provide a variety of β‐amino ketones not only from aromatic aldehydes but also from α,β‐unsaturated aldehydes mainly with syn ‐selectivity in high yields up to 99%.