NaNO2/I2 as an alternative reagent for the synthesis of 1,2,3-benzotriazin-4(3H)-ones from 2-aminobenzamides

An efficient transformation of 2-aminobenzamides to 1,2,3-benzotriazin-4(3H)-ones in the presence of sodium nitrite (NaNO2) and Iodine (I-2) is described. The reaction is proposed to proceed via formation of nitrosyl halide that induces nitrosylation of the amino group of 2-aminobenzamide leading to diazotization followed by intramolecular cyclization. (C) 2018 Elsevier Ltd. All rights reserved.