Synthesis of Dibenzo[f,h][1,2,4]triazolo[3,4-b]quinazolines via a Two-Step Route with Water as the Only By-Product

Abstract

Microwave-promoted cyclocondensation of isoflavones with 3-amino[1,2,4]triazole gave 6-phenyl-7-(2-hydroxyphenyl)-1,2,4triazolo[4,3-a]pyrimidines as intermediates. Subsequent photocyclization of these intermediates delivered dibenzo[f,h][1,2,4]triazolo[3,4b]quinazolines as final products. Water was the only by-product in this two-step procedure. The products showed distinct fluorescence properties both in solution and in the solid state .