M. B. Lukyanova

Effect of complexation with lanthanide metal ions on the photochromism of (1,3,3-trimethyl-5′-hydroxy-6′-formyl- indoline-spiro2,2′-[2h]chromene) in different media

Complexation of lanthanide ions {Ln(III) ions [Tb(III), Eu(III), or Sm(III)]} with the spiropyran-derived merocyanine obtained in dark and under steady irradiation of indoline spiropyran (1,3,3-trimethyl-5′-hydroxy-6′-formyl-indoline-spiro-2,2′-[2H]chromene) induces a noticeable hypsochromic shift of about 10–110 nm of its visible absorption band concomitant with hypochromic effect and influences its thermal bleaching in the dark. The effect of lanthanide ions and medium on photochromic, spectral-and-kinetic, and luminescence properties of the spiropyran and its complexes in solution and polymer matrix of polymethylmethacrylate (PMMA) is studied. Efficient energy transfer from the spiropyran moiety results in efficient typical luminescence from the Ln(III) ion that becomes more pronounced in polar nonalcoholic solvents and PMMA solid matrix. Moreover, luminescence mappings for pattern recognition analysis have been obtained from which the nature of the solvent and/or the ligand is clearly identified.

Solid state photochromism of spiropyrans

A series of spiropyrans possessing photochromic properties in solid state were investigated. UV irradiation (λmax=365 nm) of the thin vacuum deposited spiropyran films results in conversion of the colorless form to the photocolored one. The reaction is photochemically and thermally reversible. The photochromic activity of the solid material and polystyrene matrix has been compared. Raman spectroscopy has been used for studying the influence of metallic surface on the adsorbed spiropyran layers.

Studies of structure and photochromic properties of spiropyrans based on 4,6-diformyl-2-methylresorcinol

Indoline-derived spiropyrans, the precursors of nonsymmetric bis-spiropyrans, which are the promising prototypes of multistate molecular switches, were synthesized based on 4,6-diformyl-2-methylresorcinol. Molecular structure of one of these compounds was studied by X-ray diffraction analysis. Photochemical studies showed the presence of photochromic properties in the obtained spiropyrans at room temperature.

The Effect of Tb and Sm Ions on the Photochromic Behavior of Two Spiropyrans of Benzoxazine Series in Solution

The photochromism of [7-hydroxy-8-formyl-3-methyl-4-oxospiro[1,3-benzoxazin-2,2-[2H-1]benzopyran],SP(I),[7-hydroxy-8-formyl-3-benzyl-4-oxospiro[1,3-benzoxazin-2,2-[2H-1]benzopyran] SP(II) and their coordination with Tb3

Spiropyrans Containing the Reactive Substituents in the 2H-Chromene Moiety

Some spiropyrans containing functional substituents in the [2H]-chromene part of the molecule were synthesized and their photochromic properties in solution and solid state were investigated. The presence of the formyl group in the [2H]-chromene fragment enhances the possibility to show photochromic properties in solution.

Investigation of a new product of a condensation reation between 1,2,3,3-tetramethylindolenilium perchlorate and 2,6-diformyl-4-methyl-phenol

A new spiropyran salt in which the positive charge is localized on the nitrogen atom of the indoline moiety and the negative charge is localized on the ClO4− group is synthesized. The structure of the compound is determined by the single crystal X-ray diffraction analysis.

Theoretical and Experimental Study of New Photochromic Bis-Spiropyrans with Hydroxyethyl and Carboxyethyl Substituents

Two new asymmetrical bis-spiropyrans with nonequivalent spiropyran units have been investigated. Hydroxyethyl and carboxyethyl substituents have been used to improve thermal stability of the photoinduced merocyanine forms of the bis-spiropyrans. 2-Hydroxyethyl substituted compound is characterized by 4 times more stable merocyanine isomer. 2-Carboxyethyl substituent in the hetarene part enables chelation by metal ions and controllably stabilizes the merocyanine from thermal decay. As a result of theoretical modeling and photochemical experiments, it was shown that obtained compounds are perspective prototypes for multistate light-driven switches with improved stability of photoinduced forms.

Photochromism of the Spiropyran Thin Solid Films

ABSTRACT New spiropyrans of indoline and benzoxazinone series were synthesized. Photochromic properties of this compounds in thin solid films have been investigated.

New indoline spiropyrans containing azomethine fragment

The new spiropyran systems with an azomethine bridge were synthesized from a spiropyran containing aminogroup at 6′ position of the benzopyran fragment and substituted aromatic aldehydes. The chemical structure of compounds is confirmed by elemental analysis data, NMR (1H and 13C) and IR spectroscopy. Photochemical studies revealed the presence of photochromic properties at room temperature for one of the obtained spiropyrans.

Photo- and Thermochromic Spiropyrans 42.* The Effect of Structural Factors on the Photochromic Properties of Indolinospiro-Pyrans Containing a Condensed Furan Fragment

Syntheses are reported for a series of N-substituted indolinospiropyrans containing a fused furan fragment in the benzopyran part of the molecule. The structure of these compounds was established by IR and multinuclear NMR spectroscopy. A study was carried out on the effect of the fused benzene ring and bulky N-benzyl substituent on the photochromic properties of these compounds in solution and in a polymer matrix. Dynamic NMR spectroscopy was used to study the thermally induced isomerization of the N-benzyl derivative.