Annulation of Diaryl(aryl)phosphenes and Cyclic Imines to Access Benzo-δ-phospholactams.

Microwave-assisted annulation of cyclic imine dibenzo[b,f][1,4]oxazepines and diaryl(aryl)phosphenes generated from diazo(aryl)methyl(diaryl)phosphine oxides through the Wolff rearrangement accesses pentacyclic benzo-δ-phospholactams, 4b,16-dihydrodibenzo[b,f]benzo[4,5][1,2]azaphosphinino[1,6-d][1,4]oxazepine 15-oxides, in good yields.