Published data on the synthesis and structural modification of spiropyrans and bisspiropyrans and production of the heteroanalogs of spiropyrans are classified and analyzed. The chemical characteristics of spiropyrans, including complexation of the open-chain isomers and cyclic forms are examined. Special attention is paid to the photochromic characteristics of spiropyrans at interfaces between phases.

Optical memory devices based on photoswitchable OFETs comprising light sensitive layers of photochromic spiropyran salts revealed advanced electrical characteristics and superior stability.

Spectral properties and photochromic behavior of a series of novel 1',3',3'-trimethyl-1,2-tetramethylenespiro[7H-furo(3,2-f)-(2H-1)-benzopyran-7,2'-indolines] 1-4 have been studied. The mechanism of the photoinitiated ring-opening reaction involves the formation of an acoplanar cis-cisoid intermediate, the lifetime of which in the case of 6-(tert-butyl) derivative 4 is long enough to observe its absorption and fluorescence spectra under conditions of continuous irradiation. The occurrence of the intermediate on the reaction paths of the thermal and photochemical ring-opening processes has been also shown by the DFT and CIS calculations. The TD-B3LYP/6-31G//HF/6-31G calculated spectrum of the intermediate well matches that observed experimentally. For spiropyran 3 with a 6-NO(2) group, kinetic and activation parameters of the photoinitiated coloration and dark bleaching reactions have been determined.

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.

For Abstract see ChemInform Abstract in Full Text.

No abstract

No abstract

No abstract