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81.
Serguei O. Besugliy Anatoly V. Metelitsa Valerii Z. Shirinian Mikhail M. Krayushkin Denis M. Nikalin Vladimir I. Minkin 《Journal of photochemistry and photobiology. A, Chemistry》2009,206(2-3):116-123
Photochromic properties of novel spirooxazines of the thienopyrroline series have been studied in comparison with those of an indoline analogue. Solvatochromism of the merocyanine photoisomers has been investigated using the Kamlet–Taft model. It has been found that inversion of the trends in the solvatochromic behavior of the spirooxazines takes place when passing from non-protogenic to protic solvents. Thienopyrroline spirooxazines possess relatively poor fatigue resistance. The origin of the processes causing their photodegradation has been studied. 相似文献
82.
N. A. Voloshin E. B. Gaeva A. V. Chernyshev A. V. Metelitsa V. I. Minkin 《Russian Chemical Bulletin》2009,58(1):156-161
Photochromic spiro[indoline-benzopyrans] containing 4,5-diphenyloxazolyl group at position 8 of the benzopyran fragment have
been obtained. New diphenyloxazolyl-substituted spiropyrans manifest considerably higher thermal stability of the merocyanine
isomers than their naphthopyran analogs. 相似文献
83.
P. V. Levchenko E. N. Shepelenko L. G. Kuz’mina N. I. Makarova A. V. Metelitsa V. P. Rybalkin V. A. Bren’ V. I. Minkin 《Russian Journal of Organic Chemistry》2009,45(9):1382-1385
Reactions of (2-chloro-1-methyl-1H-indol-3-yl)-2-oxoacetyl chloride with alk-3-enoic acids gave the corresponding 6-substituted 5-methyl-5,6-dihydrocyclohepta[b]indole-9,10-dicarboxylic anhydrides which showed fluorescent properties. 相似文献
84.
N. A. Voloshin A. V. Chernyshev S. O. Bezuglyi A. V. Metelitsa E. N. Voloshina V. I. Minkin 《Russian Chemical Bulletin》2008,57(1):151-158
The Duff formylation of 5-bromo- or 5-chloro-8-hydroxyquinoline leads to the corresponding 7-formyl derivatives, condensation of which with 2-methyleneindolines or 3H-indolium halides in the presence of a base afforded new photochromic 6′-halo-substituted spiro[indoline-2,2′-2H- pyrano[3,2-h]quinolines]. Thermal and photo-induced isomerization of compounds obtained have been investigated by 1H NMR and UV spectroscopy. 相似文献
85.
M. I. Zakharova V. Pimienta A. V. Metelitsa V. I. Minkin J. C. Micheaua 《Russian Chemical Bulletin》2009,58(7):1329-1337
This review focuses on the results of the studies of metal ion complexation by spiropyrans published mostly in recent years.
Introduction of ionophore substituents in the molecules of photochromic spiropyrans induces a reasonably strong bonding in
the complexes of these compounds with metal ions. The degree of complexation depends on the state (open or closed) of the
photochromic spiropyran fragment. Directed synthesis of structures able to form complexes with metal ion requires knowledge
of structure-property relationships based, among other, on the studies of the compounds synthesized earlier. This requires
accurate determination of thermodynamic and kinetic parameters of complex formation. Difficulties of such quantitative analysis
due to the presence of several interrelated equilibria in the system are discussed. 相似文献
86.
Voloshin N. A. Metelitsa A. V. Micheau J.-C. Voloshina E. N. Besugliy S. O. Vdovenko A. V. Shelepin N. E. Minkin V. I. 《Russian Chemical Bulletin》2003,52(5):1172-1181
A procedure was developed for phase-transfer catalyzed alkylation of 5-hydroxyindolenine and 9"-hydroxy-substituted spiro[indoline-2,3"-naphtho[2,1-b]oxazines] by alkyl halides. New 9"-hydroxy- and 9"-alkoxy-substituted spironaphthooxazines, spirooxazinyloxyacetic acids, and their esters containing substituents with different length of the carbon chain in the indoline moiety were synthesized. The influence of the substituents on the spectroscopic properties of the starting and colored forms and the kinetic characteristics of photochromic transformations of 9"-substituted spironaphthooxazines in solutions and polymeric films was investigated. The bipolar merocyanine forms of spirooxazines were found to produce H-aggregates. 相似文献
87.
I. M. Andreeva E. A. Bondarenko N. V. Volubushko M. I. Knyazhanskii E. A. Medyantseva A. V. Metelitsa V. I. Minkin B. Ya. Simkin 《Chemistry of Heterocyclic Compounds》1980,16(8):799-806
A number of N-aryl- and N-alkylimines of 2-hydroxy-5,6-benzocinnamaldehyde were synthesized. The cyclic 2-amino-2H-chromene structure in nonpolar solvents was established for them by IR, UV, and PMR spectroscopy. It is shown that the transition to polar solvents leads to the establishment of a tautomeric ring-chain equilibrium. The equilibrium thermal transformations and phototransformations of some N-aryl- and N-alkylimines were studied.Communication 12 from the series Photo- and Thermochromic Spirans. See [1] for Communication 11.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1035–1044, August, 1980. 相似文献
88.
89.
90.
Energetics and structural mechanisms of photochemical processes in molecules of aldonitrone vinylogs
A. V. Metelitsa M. I. Knyazhanskii N. V. Volbushko V. S. Nedzvetskii V. I. Minkin 《Chemistry of Heterocyclic Compounds》1990,26(10):1145-1149
Depending on the multiplicity of the excited state, alternative photoreactions are realized in methoxy and acetoxy derivatives of aldonitrone vinylogs: diabatic nitrone-oxazypyridone rearrangement in the first excited singlet state and E-Z isomerization involving the C=N bond in the triplet state. In the case of aldonitrone vinylogs with an o-hydroxy group in the -aryl ring one observed adiabatic proton transfer from the hydroxy group to the azotoxido group with a subsequent diabatic reaction involving cyclization to the 2H-chromene structure. The same transfer is also realized in the triplet state. The quantum yields were determined, and the energies of activation of the photoreactions and the reverse thermal processes were evaluated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1373–1378, October, 1990. 相似文献