N-[4-(3-Methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]-N′-pyridin-2-ylmethylene-chloro-acetic acid hydrazide: Synthesis and configurational assignment based on X-ray, 1H, and 13C NMR and theoretical calculations

In this study, quantum chemical calculations based on the density functional theory have been carried out to examine the effects of N -[4-(3-methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]- N ′-pyridin-2-ylmethylene- chloro-acetic acid hydrazide. The calculated values are compared with the experimental data available for these molecules as a mean of validation of our proposed chemistry model. Aided by normal coordinate analysis and potential energy distributions, a confident vibrational assignment of all fundamentals is proposed herein. Additional support is given by 1 H and 13 C NMR spectra recorded with the sample dissolved in CDCl 3 and by predicted chemical shifts at the B3LYP/6-31G( d )/6-311G+( d ) levels obtained using the gauge-invariant atomic orbital method. The calculated HOMO and LUMO energies also confirm that the charge transfer occurs within the molecule. Thiazole-based compounds are potential storehouse for exploiting CH···O and CH···N hydrogen bonding interactions for molecular self-assembly.