Photochromism and hydrolysis of aromatic Schiff base N,N'-bis(salicylidene) -p-phenylenediamine (BSP) studied in heterogeneous environments

A photochromic symmetric Schiff base, N,N'-bis(salicylidene)-p- phenylenediamine has been studied by means of stationary spectroscopic absorption and emission techniques in the IR and UV-vis spectral range in heterogeneous environments: microporous and mesoporous molecular sieves and micellar systems. The intermolecular hydrogen bonds between the molecule studied and silanol groups in mesoporous material have led initially to the stabilization of the cis-keto tautomer and later to a very effective hydrolysis. Persisting two-step color changes have been found to occur after the UV irradiation of the molecule studied encapsulated in microporous and mesoporous molecular sieves. © 2008 Springer Science+Business Media B.V.