A new type of Baylis–Hillman adducts derived from chlorovinyl aldehydes were prepared via Vilsmeier reaction of ketones with a bis (trichloromethyl) carbonate (BTC)/DMF system to construct chlorovinyl aldehydes, followed by sonochemical Baylis–Hillman reaction under solvent-free conditions. The stereoselective bromination of these new compounds with a Br2- Ph3P system has been achieved efficiently with good to excellent yields under mild ...
