Remarkable thermally stable open forms of photochromic new N-substituted benzopyranocarbazoles

摘要: New N-substituted benzopyranocarbazoles were synthesized and their photochromic properties, under continuous near-UV irradiation, are described. Besides a remarkable sensitiveness to solar light, N-methyl N-benzyl derivatives give rise particularly stable coloured open forms. The structure of these photoisomers was characterized through NMR spectroscopy. According our results, it possible, after UV accumulate more than 90% the long-lived TT-isomer. At ambient temperature, TT state fully photobleachable by visible light no significant degradation observed during cycling. This property opens range potential applications for in photoswitchable devices.