2nd International Conference on Chemo and Bioinformatics ICCBIKG 2023 (625-628)
АУТОР(И) / AUTHOR(S): Dušan P. Malenov, Jelena P. Blagojević Filipović, Snežana D. Zarić
Е-АДРЕСА / E-MAIL: malenov@chem.bg.ac.rs
DOI: 10.46793/ICCBI23.625M
САЖЕТАК / ABSTRACT:
The effects of alkyl substituents on stacking interactions of aromatic ligands in organometallic compounds were studied on two most common ligands with substituents –pentamethylcyclopentadienyl (Cp*) and 1-methyl-4-sopropylbenzene (p-cymene). The analysis of geometries of interactions found in crystal structures deposited in the Cambridge Structural Database indicated that substituents are involved in interactions with aromatic rings, indicating the combination of stacking and C-H/π interactions for both Cp* and p-cymene ligands. Quantum chemical calculations on p-cymene half-sandwich ruthenium(II) compound showed that additional C-H/π interactions significantly strengthen stacking interactions, since the B97D2/def2-TZVP interaction energy between two p-cymene complexes is -7.56 kcal/mol, while the interaction energy between two corresponding benzene complexes is -3.93 kcal/mol. Ruthenium p-cymene complexes can engage in stacking interactions with large horizontal displacements combined with interactions between the substituents, with a significant interaction energy of -4.57 kcal/mol. These studies show that substituents strengthen stacking interactions of coordinated aromatic rings and modulate their geometries by providing additional simultaneous interactions.
КЉУЧНЕ РЕЧИ / KEYWORDS:
stacking interactions, C-H/π interactions, organometallic compounds, crystal structures, density functional theory
ЛИТЕРАТУРА / REFERENCES:
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