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Information × Registration Number 0214U005363, 0113U002934 , R & D reports Title Synthesis and spectral properties of new deeply coloured merocyanine dyes based on non-traditional acceptors popup.stage_title Head Kulinich Andrii Volodymyrovych, Кандидат хімічних наук Registration Date 18-12-2014 Organization Institute of Organic Chemistry National Academy of Sciences of the Ukraine popup.description2 Objective. Molecular design, synthesis and spectral investigation of deeply colored merocyanine dyes with non-traditional acceptor moieties. Di-, tetra- and hexamethinemerocyanines with indole moiety as a terminal electron donating groups derivatives of di-, tri- and tetranitrofluorene were modeled and synthesized. Di-, tetra- and hexamethinemerocyanines based on 2,4,5,7-tetranitrofluorene 2,7-bis-(alkoxysulfonyl)-4,5-dinitrofluorene and various electron-donating heterocycles were obtained. It is found that the absorption spectra of the synthesized compounds are characterized by the presence of several intense absorption bands in the visible and near-IR spectral regions. DFT and TDDFT quantum-chemical calculations of the electronic structure and electronic transitions in the molecules of synthesized dyes allowed to interpret the nature of their long-wavelength absorption bands. The photophysical properties of merocyanines based on malononitrile and various electron-donating heterocycles were investigated. It is shown that the lifetime is maximal for merocyanine photoisomers which electronic structure is close to the neutral polyene. That can be explained by the reduced orders of those polymethine chain bonds around which photoisomerization takes place. It is shown that merocyanine photoisomers can absorb both at longer and at shorter wavelengths compared with the corresponding all-trans-isomer. Sensitized population of the triplet level allowed measuring their T-T-spectra and the lifetimes in the triplet state. It is shown that the photostability of merocyanines deteriorates with increasing electron-donating ability of heterocyclic terminal groups. Boron-dipyrromethenes (BODIPY) with chlorine atoms and the series merocyanines based on them were designed and synthesized. Analysis of the absorption and fluorescence spectra of these compounds in solvents of various polarity allowed tracing the transformation of BODIPY chromophore system into polymethine one via an intermediate polyene state. Also the BODIPY based asymmetric anionic polymethines were synthesized. As a result, it was shown that BODIPY core has large effective length and is promising for synthesis of deeply colored merocyanines with medium and high electron-donating heterocycles. Areas of application. Solar energy, registration and representation of optical information, optoelectronics, nonlinear optics, chemosensors for biology and medicine. Product Description popup.authors Кулініч Андрій Володимирович Курдюкова Ірина Володимирівна Якубовський Віктор Петрович popup.nrat_date 2020-04-02 Close