Reactions of pyrazole-3(5)-diazonium salts with 4-hydroxy-2Н-chromen-2-one and isochroman-1,3-dione

Abstract

Derivatives of a previously unknown heterocyclic system 6Н-chromeno[4,3-e]pyrazolo[5,1-c][1,2,4]triazin-6-one were obtained via reaction of pyrazole-3(5)-diazonium salts with 4-hydroxy-2Н-chromen-2-one. Analogous reactions with isochroman-1,3-dione are followed by recyclization leading to the formation of 2-(4-hydroxypyrazolo[5,1-c][1,2,4]triazin-3-yl)benzoic acids.