One-pot synthesis of N-substituted benzannulated triazoles via stable arene diazonium salts?

Organic & Biomolecular Chemistry Pub Date: 2021-06-22 DOI: 10.1039/D1OB00968K

Abstract

A mild and effective one-pot synthesis of 1,2,3-benzotriazin-4(3H)-ones and benzothiatriazine-1,1(2H)-dioxide analogues has been developed. The method involves the diazotisation and subsequent cyclisation of 2-aminobenzamides and 2-aminobenzenesulfonamides via stable diazonium salts, prepared using a polymer-supported nitrite reagent and p-tosic acid. The transformation was compatible with a wide range of aryl functional groups and amide/sulfonamide-substituents and was used for the synthesis of pharmaceutically important targets. The synthetic utility of the one-pot diazotisaton–cyclisation process was further demonstrated with the preparation of an α-amino acid containing 1,2,3-benzotriazin-4(3H)-one.

Graphical abstract: One-pot synthesis of N-substituted benzannulated triazoles via stable arene diazonium salts
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