Regioselective addition of the prenal potassium dienolate onto α,β- unsaturated aldehydes. A short access to polyenaldehydes

Article abstract of DOI:10.1016/S0040-4039(98)01544-5

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.