Asymmetric organocatalytic cascade Michael/hemiketalization/retro-Henry reaction of beta,gamma-unsaturated ketoesters with alpha-nitroketones

An unprecedented enantioselective organocatalytic Michael/hemiketalization/retro-Henry cascade sequence is described, which catalyzed by a simple bifunctional indane amine-thiourea catalyst. This process provides a new route to the enantioselective synthesis of 5-nitro-pent-2-enoates, a precursor to alpha-ketolactam.