Light absorption and stability properties of some near-IR indamine dyes related to Bindschedlers green

Symmetrical indamine (quinoneimine) cationic dyes related to Bindschedlerʹs Green have been synthesised by condensing 3-substituted NN-dialkylanilines with their corresponding 4-nitroso derivatives in acetic anhydride. The light absorption and general stability properties of the dyes have been examined. ©