Enantioselective Hetero-Diels–Alder Reaction and the Synthesis of Spiropyrrolidone Derivatives

An
efficient enantioselective hetero-Diels–Alder reaction
was developed under catalysis of a chiral copper complex. A variety
of spiropyrrolidones, which bear a tetra-substituted carbon stereocenter,
can be obtained in good yields with excellent enantioselectivities
by virtue of this method. Furthermore, a substrate-dependent reaction
pathway was proposed on the basis of the isolated intermediates.