Secondary Amine/N-Heterocyclic Carbene Catalyzed Cascade Sequence

Significance

A one-pot, asymmetric multicatalytic formal [3+2] reaction between α,β-unsaturated aldehydes 3 and 1,3-dicarbonyl compounds 4 is described. A combined use of secondary amine catalyst 1 and N-heterocyclic carbene catalyst 2 provides rapid access to functionalized cyclopentanones 5 and bicycles 6 and 7 containing three contiguous stereocenters. Products were obtained in good yields, with high enantioselectivity and moderate diastereoselectivity.