Synthesis of 2 and 6-triazolylthiazolo[4,5-b]quinoxaline derivatives and their application as fluorescent disperse dyes

Synthesis of 2-triazolylthiazolo4,5-b]quinoxaline derivatives was achieved by diazotisation of 2-aminothiazolo4,5-b]quinoxaline and its 6-nitro derivative using orthophosphoric acid and sodium nitrite with a trace of nitric acid, coupling with suitable aromatic amines and subsequent cyclisation of the resulting ortho amino azo compounds. Diazotisation of 2,6-diaminothiazolo4,5-b]quinoxaline with concentrated hydrochloric acid and sodium nitrite and subsequent coupling and cyclisation resulted in the 6-triazolylthiazolo4,5-b]quinoxaline derivatives. These compounds were applied on polyester as fluorescent disperse dyes.