Diastereoselective control of intramolecular aza-Michael reactions using achiral catalysts.

An intramolecular aza-Michael reaction with a Cbz carbamate and an enone is reported to result in 3,5-disubstituted nitrogen-containing heterocycles. Either cis or trans isomers were obtained selectively using chiral substrates and an achiral Pd(II) complex or strong Brønsted acid catalysis. A range of substrates undergoes these selective transformations. Functionalization of the resulting products yielding bicyclic heterocycles is also demonstrated.