Abstract Base-promoted reaction of ketones and diethyl (diazomethyl) phosphonate in the presence of allylic amines affords allylic enamines in good yields. These enamines undergo [3, 3]-sigmatropic rearrangement upon alkylation and heating at 80 C to iminium salts which can be hydrolysed to aldehydes. The procedure allows generation of quaternary carbon centers under mild reaction conditions.