Palladium-catalyzed nucleophilic allylic substitution of Morita-Baylis-Hillman adducts with enamines: Synthesis of 1,5-dicarbonyl compounds

An efficient nucleophilic allylic substitution of a variety of Morita-Baylis-Hillman adducts with enamines catalyzed by Pd(OAc)2 in the presence of ZnBr2 as a promoter is described in the present study. The reaction gives SN2-type 1,5-dicarbonyl compounds that may subsequently undergo an intramolecular conjugate addition onto the enone moiety affording the corresponding 1,4-adducts. All the synthesized compounds have been isolated in moderate to good yields and fully characterized.