Synthesis of new 1H-tetrazoles and 1,2,3-triazoles via reactions of 3(,5)-(di)chloro-2H-1,4-(benz)oxazin-2-ones with sodium azide or diazocompounds.

3,5-dichloro-2H-1,4-oxarin-2-ones and 3-chloro-2H-1,4-benzoxazin-2-ones are reacted with bifunctional reagents as sodium azide and diazocompounds to yield bi(tri)cyclic tetrazolo- or triazolo fused intermediates via an intramolecular cyclisation reaction. Conversion of these lactone inter-mediates with various nucleophiles generates new substituted 1H-tetrazoles or 1,2,3-triazoles useful for pharmacological screening and for further elaboration via the alpha-chloroketone substituent at N-1. (C) 1996 Elsevier Science Ltd