Construction of Distant Stereocenters by Enantioselective Desymmetrizing Carbonyl–Ene Reaction

An efficient desymmetrizing
carbonyl–ene reaction of 1-substituted
4-methylenecyclohexanes with glyoxal derivatives was thus executed
by a chiral N,N′-dioxide/NiII catalyst, providing facile access to cyclohexene derivatives
bearing two remote 1,6-related stereocenters. This distal stereocontrol
methodology originates from the efficient interaction between the
catalyst with enophiles, discrimination of the two chair conformations
of olefinic components, and the intrinsic six-membered transition-state
structure of ene process.