A highly asymmetric, Lewis acid-catalysed Diels–Alder reaction using optically active 2-(3-tolyl p-sulfinyl)furyl α,β-unsaturated ketones as a dienophile
Abstract
The Diels–Alder reaction of chiral 2-(3-tolyl p-sulfinyl)furyl α,β-unsaturated ketones 3 and 4 with cyclopentadiene in the presence of a Lewis acid proceeds smoothly to give the corresponding endo adducts 5a and 6a, respectively, in excellent yield with high diastereoselectivity.