Structural Characterization, Theoretical Investigation and Hirshfeld Surface Analysis of 2,6-(E,E)-bis((thiophene-2-yl)methylene)cyclohexanone

Authors : Gül YAKALI, Abdullah BİÇER, Günseli Turgut CİN

Pages : 47-58

Doi:10.33435/tcandtc.457453

View : 15 | Download : 8

Publication Date : 2019-12-15

Article Type : Research Paper

Abstract :The bisinsert ignore into journalissuearticles values(chalcone); compound, 2,6-insert ignore into journalissuearticles values(E,E);-bisinsert ignore into journalissuearticles values(insert ignore into journalissuearticles values(thiophene-2-yl);methylene);cyclohexanone, has been synthesized and characterized by FTIR, 1 H-NMR, 13 C-NMR techniques, X-ray structure analysis. The optimized molecular structure of the studied compound is calculated using DFT/B3LYP with 6-31G insert ignore into journalissuearticles values(d,p); level. The calculated geometrical parameters are in good agreement with the experimental data obtained from our reported X-ray structure. The calculated IR fundamental bands, 1 H and 13 C NMR chemical shifts of the compound   were assigned and compared with the experimental data. Additionally, frontier molecular orbital energies insert ignore into journalissuearticles values(HOMO, LUMO);, their energy gap insert ignore into journalissuearticles values( , molecular electrostatic potential analysis of the compound have been calculated by the same method. The molecular electrostatic potential insert ignore into journalissuearticles values(MEP); was used to visualize the charge distribution on the molecule. In addition, the intercontacts in the crystal structure are analyzed using Hirshfeld surfaces computational method. The title compound insert ignore into journalissuearticles values(C 16 H 14 OS 2 ); crystallizes in the monoclinic chiral space group P21/c with a= 15.0492insert ignore into journalissuearticles values(10); Å, b= 12.0085insert ignore into journalissuearticles values(9); Å, c= 7.6283insert ignore into journalissuearticles values(6); Å, β = 95.883insert ignore into journalissuearticles values(7); o , V= 1371.31insert ignore into journalissuearticles values(17); Å 3 , D calc = 1.387 g/cm 3 . The central cyclohexanone ring has a flattened chair conformation and t he substituents at the vinyl group of each chalcone moiety exhibit a trans insert ignore into journalissuearticles values(entgegen); disposition, and the two thiophene rings adopt a syn orientation and are located on the both side of the cyclohexanone. The asymmetric unit of the title compound, C 16 H 14 OS 2 , contains one-half of a molecule. The other half of the molecule is generated with insert ignore into journalissuearticles values(x,y,-z);   symmetry operator. In the molecule there are two weak C-H…S and C-H…O intramolecular and only C-H…O intermolecular hydrogen bonds. In addition, π…π interactions are found in the crystal structure between the thiophene rings.
Keywords : Bis chalcone, X ray crystallography, DFT