Study on the mechanistic classes of fluorescence quenching of tryptanthrin-malononitrile adduct by aniline.

Mechanistic studies of the fluorescence quenching of 2-(2-chloro-12-oxoindolo[2,1-b]quinazolin-6(12H)-ylidene)malononitrile (2CTMA) with aniline, using solvent mixtures of acetonitrile and 1,4-dioxane at room temperature, by steady-state and time-resolved methods is reported here. It was confirmed that, with the use of the sphere of action static quenching model and finite sink approximation model, that the bimolecular quenching reactions are due to the presence of both dynamic and static quenching processes.