A novel reductive cross-coupling reaction of 2-nitrobenzoic hydrazides and aldehydes or ketones promoted by the low-valence titanium reagent: an access to 2,3,4,5-tetrahydro-1H-1,3,4-benzotriazepine-5-one derivatives

摘要

A short and facile synthesis of a series of 2,3,4,5-tetrahydro-1H-1,3,4-benzotriazepine-5-one derivatives was accomplished in good yields via the intermolecular reductive coupling reaction of 2-nitrobenzoic hydrazides and aldehydes or ketones promoted by the low-valence titanium reagent (TiCl4/Zn system). Structures were established on the basis of elemental analysis, IR and H-1 NMR spectra.