Facial selectivity in the Diels–Alder reactions of cis-cyclohexa-3,5-diene-1,2-diol and derivatives with N-phenylmaleimide
Abstract
N-Phenylmaleimide adds to cis-cyclohexa-1,3-diene-1,2-diol and its derivatives preferentially to the face of the diene syn to the oxygen substituents; this effect is less pronounced in the more reactive, cyclic derivatives.