Abstract The potassium dienolate of prenal obtained by treatment of the corresponding dienoxysilane with tBuOK was reacted with enaldehydes. In all cases a γ-specific reaction occurs. According to the reaction conditions a γ; 1,2 or a γ; 1,4 coupled product was selectively obtained with enals. The γ; 1,2 reaction provided an efficient prenylation procedure. A short two-step synthesis of retinal is described.