An Expedient Synthesis of β-Phenyl Substituted Baylis-Hillman and Aza-Baylis-Hillman Adducts

During the last two decades notable improvements in the Baylis-Hillman chemistry have been achieved in view of its reaction rate and synthetic applications of Baylis-Hillman adducts.1 However, synthesis of β-branched Baylis-Hillman adducts has still remained as a difficult task.2,3 Synthesis of these compounds has been carried out either via the vinyl-alumination of activated carbonyl compounds2a-c or SmI2-mediated reaction of α-halo-α,β-unsaturated esters with carbonyls.2d However, these methods suffer from the use of expensive/moisture-sensitive reagents and α,β-acetylenic esters as starting materials which are not easily accessible. For the synthesis of poly-substituted benzenes4a-c and pyridines4d we required β-phenyl Baylis-Hillman adducts such as 3a. Thus, we examined the synthesis of β-phenyl Baylis-Hillman adduct by following the successive Friedel