Photochemistry and excited state prototropic behaviour of 8-amino 2-naphthol

In the present work, photophysical behaviour of 8-amino 2-naphthol in various solvents as well as at various pH values has been investigated. Various ground and excited state species are noticed. It exhibits a completely different photo prototropic behaviour as compared to its parent molecule 2-naphthol. The spectral and transient studies indicate that at lower pH values, equilibrium between cation and neutral exists in the excited state. At neutral pH some peculiar behaviour in its spectral properties is noticed.

Figure optionsDownload as PowerPoint slideHighlights
► Spectral and time resolved properties of 8-amino-2-naphthol are investigated.
► Some interesting pH dependent features for this compound are noticed.
► At lower pH (1.7), cation/neutral dynamic equilibrium exists in the excited state.
► At neutral pH, it exhibits larger Stokes shifted emission.
► The spectral signatures indicate various emitting/absorbing species.