1,5-Benzoheteroazepines through eco-friendly general condensation reactions

Condensation reactions of o-phenylenediamine and 2 equiv of acetone produce biaryl-substituted 1,5-benzodiazepines. The synthetic protocol shows general applicability since similar reaction of o-phenylenediamines, o-aminophenol, and o-aminothiophenol with ketones or chalcones leads to formation of functionalized 1,5-benzoheteroazepines in good to excellent yields. The synthetic protocol fulfills many green-chemical requirements using simple MW-assistance to promote the activation of ketones and the eco-compatible Er(III) triflate as activator of chalcones.