Enantioselective Construction of the Biologically Significant Dibenzo[1,4]diazepine Scaffold via Organocatalytic Asymmetric Three-Component Reactions

The first catalytic asymmetric construction of the biologically important dibenzo[1,4]diazepine scaffold has been established via SPINOL-derived chiral phosphoric acid-catalyzed three-component reactions of aldehydes, 1,2-phenylenediamines and cyclohexane-1,3-diones, which afforded structurally complex and diverse dibenzo[1,4]diazepines in high yields and good enantioselectivities (up to 98% yield, 92:8 er). This transformation also represents the first catalytic asymmetric version of this three-component reaction and provides an easy access to structurally rigid seven-membered chiral heterocycles.