π-Facial stereoselectivities in Diels–Alder cycloadditions to a dissymmetric cyclohexa-1,3-diene moiety in a novel, caged polycyclic framework
Abstract
Novel polycyclic 1,3-dienes 4 and 5 have been synthesised and shown to undergo Diels–Alder cycloadditions exclusively from the carbonyl face. Steric environment seems to be predominantly responsible for the observed stereochemistry.