Stereoselectivity, regiwelectivity, and structural selectivity of the thermal ene reactions of diethyl oxomalonate are strongly determined by steric approach control. For a series of 1- arylcyclopentenes thermal ene reactions only show a small enhancement of rate by electron- donating substituents (p=-1.2* 0.2). Lewis acid catalysis is described which allows ene reactions of diethyl oxomalonate under thermally mild conditions. Furthermore, catalysis ...
