Synthesis, molecular and crystal structure analysis of 2-bromo-4-chloro-6-{[4-(3-methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]-hydrazonomethyl}-phenol by experimental methods and theoretical calculations

A novel hydrazone derivative 2-bromo-4-chloro-6-{[4-(3-methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]-hydrazonomethyl}-phenol was synthesized and characterized by IR, UV–Vis spectroscopy and X-ray single crystal diffraction. The compound crystallizes in monoclinic space group P21/c with a = 8.0862(3) Å, b = 7.6168(1) Å, c = 37.3168(12) Å and β = 91.186(1)°. In addition, the molecular geometry and vibrational frequencies of the title compound in ground state have been calculated by using density functional theory (DFT) at B3LYP level with 6-31G and 6-31G(d, p) basis sets. The geometrical parameters of the title compound obtained from XRD studies are in good agreement with the calculated values. The analysis of IR spectrum supported by DFT calculations was particularly devoted to the manifestations of hydrogen bonding in the νstr(NH) and νstr(OH) vibrations. To determine the conformational flexibility for a selected torsion angle τ(C6C1C7N1) one-dimensional potential energy scan was performed using AM1 in the full range of 0–360° increasing of 10°. UV–Vis absorption spectrum of the compound has been compared to theoretical spectrum (vertical excitations) computed by time dependent density functional theory (TD-DFT). Besides frontier molecular orbitals and molecular electrostatic potential map analysis were investigated by theoretical calculations.

► We investigate molecular and crystal structure of the new hydrazone derivative. ► Crystal structure is stabilized by NH⋯O, OH⋯O and CH⋯O type hydrogen bonds. ► The calculated frequencies for νstr(OH) and νstr(NH) higher the experimental ones.