Aziridinyl ketones and their cyclic anils. 10. 2,4,6-Triaryl-1,3-diazabicyclo[3.1.0]hex-3-enes

2,4,6-Triaryl-1,3-diazabicyclo[3.1.0]hex-3-enes were prepared by the reaction of α,Β-dibromochalcones with aromatic aldehydes and ammonia. The exo- and endo-isomers were isolated and characterized. X-ray structural analysis of the endo-6-(4-nitrophenyl)-2,4-diphenyl derivative was performed.