Experimental and theoretical investigation of the molecular and electronic structure of 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine

• Published in: Journal of molecular modeling 2009-12, Vol.15 (12), p.1435-1445
• Main Authors: Ozdemir, Namik, Dinçer, Muharrem, Cukurovali, Alaaddin, Büyükgüngör, Orhan
• Format: Article
• Language: English
• Subjects: Amines - chemical synthesis; Amines - chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Crystallography, X-Ray; Cyclobutanes - chemical synthesis; Cyclobutanes - chemistry; Electrons; Hydrogen Bonding; Magnetic Resonance Spectroscopy; Models, Molecular; Molecular Medicine; Original Paper; Spectroscopy, Fourier Transform Infrared; Surface Properties; Theoretical and Computational Chemistry; Thermodynamics; Thiazoles - chemical synthesis; Thiazoles - chemistry; Vibration
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-009-0509-y

The title molecule, 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine (C 20 H 21 N 3 S), was prepared and characterized by 1 H-NMR, 13 C-NMR, IR and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P 2 1 / c with a  = 9.4350(5) Å, b  = 11.2796(6) Å, c  = 18.4170(8) Å and β  = 113.378(3)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) 1 H- and 13 C-NMR chemical shift values and atomic charges distribution of the title compound in the ground state have been calculated using the Hartree–Fock (HF) and density functional method (DFT) (B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from −180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis was performed by the B3LYP/6-31G(d) method.