112213-99-7Relevant academic research and scientific papers
Photochromism in N,N'-Di(o-nitrobenzylidene)diamines
Rawat, M. S. M.
, p. 238 - 242 (2007/10/02)
Dianils of o-nitrobenzaldehyde with p,p'-phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane and benzidine have been prepared and their photochromic behaviour has been investigated in solid state, solution and rigid glassy solvents at low temperatures.There is a change in colour on irradiation by UV or sunlight in the solid state which thermally reverses into the original colour in the dark.However, on prolonged irradiation, the colour changes permanently and can not be reversed on heating.Irreversible changes have been observed when the solutions of these compounds are irradiated (365 nm).The IR and mass spectra of the irradiated samples lead to the conclusion that the permanent change in the compounds after irradiation is due to the transformation of o-nitrobenzylidene form to o-nitrosobenzanilide form.On irradiating (365 nm) the PMMA films of the dianils at -180 deg C (liquid air temperature), a characteristic concomitant band appears at 465-470 nm with the absorption band at 355 nm undergoing hypsochromic shift as well hypochromic shift.This is attributed to the formation of quinonoid form with simultaneous degradation of the compounds.
