Synthesis and properties of a novel photochromic luminophore

A photochemically bifunctional compound was obtained. Its molecule includes the spironaphthoxazine and dansylamino fragments. This compound exhibits both photochromic and luminescent properties. Its spectroscopic characteristics were studied in different solvents. The electronic systems of two constituent fragments do not interact with each other. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2802–2805, December, 2005.     

Merocyanine form of photochromic spirooxazines in acid solutions

Electronic absorption and NMR spectra of solutions of photochromic spironaphthoxazines (SNOs) were studied. The addition of an acid results in the formation of a salt of the colored form of SNO. For SNOs with nitrogen-containing electron-releasing substituents, the structure of the product that formed depends on the acid concentration being the salt of the mono- or dication.     

Aggregation of nitrosubstituted spiropyranes in polymeric films

Absorption, luminescence, and luminescence polarization spectra of associates of photochronic molecules of nitrosubstituted indolinospiropyranes in the closed form in polymeric films at high temperatures were studied. The efficiency of the formation of the associates depends on the structure of the photochrome molecules and the nature of the polymeric matrix. A scheme of phototransformations of the associates taking into account the exciting light wavelength was suggested. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 946–949, May. 1997.     

Synthesis and photochromic properties of nitro-substituted spironaphthooxazines

7-Nitro- and 8-nitroderivatives of 1,3,3-trimethylspiro[indoline-2,3-3H-naphtho[2,1-b][1,4]oxazine] were synthesized, the last of them being prepared by direct nitration. The introduction of the nitro group stabilizes a bipolar colored form, the highest stability being exhibited when the NO₂ group is the 8-position.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2576–2580, November, 1989.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.