Regioselective aza-Michael addition of azoles to 4-(diphenylphosphoryl)but-3-en-2-one

Aza-Michael reaction of (E)-4-(diphenylphosphoryl)but-3-en-2-one with mono- and bicyclic nitrogen heterocycles proceeds regioselectively in the absence of catalysts to give the corresponding ß-diphenylphosphoryl-b-azahetarylalkanones. Its reaction with imidazole in the presence of chiral organocatalysts affords the corresponding enantiomerically enriched adduct in higher yield.