A detailed experimental and computational study of monocarbohydrazones
AuthorsBožić, Aleksandra R.
Verbić, Tatjana Z.
Milcić, Milos K.
Todorović, Tamara R.
Cvijetić, Ilija N.
Radisić, Marina M.
Marinković, Aleksandar D.
Article (Published version)
MetadataShow full item record
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 Catalan 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 pK(a) 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 pathway...s. 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
Source:Arabian Journal of Chemistry, 2020, 13, 1, 932-953
- Elsevier, Amsterdam
Funding / projects:
- Study of the Synthesis, Structure and Activity of Natural and Synthetic Organic Compounds (RS-172013)
- Interactions of natural products, their derivatives and coordination compounds with proteins and nucleic acids (RS-172055)