Photochromic properties of 1,3,3-trimethyl-6′-nitrospiro (indolino-2,2′-[2H-1]benzothiopyran) in polymeric films

Conclusions An indolinobenzothiopyran with an electron-acceptor substituent- the NO₂ group- in position 6 has been synthesized, and its photochromic behavior in various polymeric matrices has been investigated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1509–1512, July, 1985.     

Inversion of configuration in the closed form of spirothiopyran molecules

Conclusions The Gvalue for the inversion of configuration of the closed form of spirothiopyrans is significantly greater than for their oxygen analogs due to steric hindrance for rotation of the rotation of the benzopyran fragment relative to the indoline fragment.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1666–1668, July, 1987.     

Photochromism and the spectral properties of bispiroanthro-bis-oxazine

The spectral and photochromic properties of bispiroanthro-bis-oxazine (bis-SAO) in toluene, DMF, and polystyrene films were investigated in the 77–300 K interval. It is shown that the long-wave part of the absorption spectrum of the starting form of the molecule is formed by three-electron transitions localized in the anthro-bis-oxazine fragment. The directions of the oscillators of these transitions relative to the nuclear. backbone of the molecule are proposed on the basis of luminescence polarization data. It is proposed that the photochromic properties of the solutions are determined by the existence of bis-SAO molecules in dimer form.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Institute of Solid State and Semiconductor Physics, Academy of Sciences of Belarus, 210023 Vitebsk. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2718–2725, December, 1992.