A detailed experimental and computational study of monocarbohydrazones
Autor: | Marina Radišić, Olivera R. Klisurić, Tamara R. Todorović, Ilija N. Cvijetić, Tatjana Ž. Verbić, Nenad Filipovic, Miloš Milčić, Aleksandra R. Božić, Aleksandar D. Marinković |
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Jazyk: | angličtina |
Rok vydání: | 2020 |
Předmět: |
General Chemical Engineering
Imine Substituent Ab initio LSER 02 engineering and technology 010402 general chemistry 01 natural sciences lcsh:Chemistry Photochromism chemistry.chemical_compound Computational chemistry Photoisomerization Quantum chemical calculation Chemistry Hydrogen bond Intermolecular force General Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences Solvatochromism lcsh:QD1-999 Intramolecular force Physical chemistry Solvent effects Intramolecular charge transfer 0210 nano-technology |
Zdroj: | Arabian Journal of Chemistry, Vol 13, Iss 1, Pp 932-953 (2020) Arabian Journal of Chemistry |
ISSN: | 1878-5352 |
Popis: | The substituent and solvent effect on intramolecular charge transfer (ICT) of twelve monocarbohydrazones (mCHs) were studied using experimental and theoretical methodology. The effects of specific and non-specific solvent–solute interactions on the UV–Vis absorption maxima shifts were evaluated using linear free energy relationships (LFERs) principles, i.e. using the Kamlet-Taft and Catalán models. Linear free energy relationships in the form of single substituent parameter equation (SSP) was used to analyze substituent effect on UV–Vis, NMR and pKa change. According to crystallographic data and quantum chemical calculations, the trans (E) form was found to be more stable. A photochromism of compounds with 2-hydroxyphenyl and 2-pyridylimino groups substituted at imine carbon atom results in E/Z isomerization due to creation of intermolecular hydrogen bond in E and Z form, respectively. Multiple stage mass spectrometry (MS-MSn) analysis was applied to define main fragmentation pathways. Furthermore, the experimental findings were interpreted with the aid of ab initio MP2/6–311 G(d,p) and time-dependent density functional (TD-DFT) methods. TD-DFT calculations were performed to quantify the efficiency of intramolecular charge transfer (ICT) with the aid of the charge-transfer distance (DCT) and the amount of transferred charge (QCT) calculation. It was found that both substituents and solvents influence electron density shift i.e. extent of conjugation, and affect ICT character in the course of excitation. Keywords: Solvatochromism, LSER, Photoisomerization, Intramolecular charge transfer, Quantum chemical calculation |
Databáze: | OpenAIRE |
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