Catalytic asymmetric construction of spiro(γ-butyrolactam-γ-butyrolactone) moieties through sequential reactions of cyclic imino esters with Morita-Baylis-Hillman bromides.

Spiro(γ-butyrolactam-γ-butyrolactone): a route to enantioenriched spiro(γ-butyrolactam-γ-butyrolactone) compounds, a valuable motif for drug discovery, was developed by use of a highly efficient copper(I)/TF-BiphamPhos-catalyzed tandem Michael addition-elimination of homoserine lactone derived cyclic imino esters with Morita-Baylis-Hillman (MBH) bromides, followed by treatment with para-toluenesulfonic acid.