Synthesis and characterization of tailor-made o-hydroxysubstituted anils through 1H NMR, ­13C NMR, SC-XRD and DFT studies for possible optoelectronic applications

Abstract

The present work reports the synthesis of two simple tailor-made anils (o-hydroxybezylidene-orthochloroaniline & o-hydroxynaphthalidene-orthochloroaniline) and their characterization by 1H & 13C Nuclear magnetic resonance(NMR), single X-ray diffraction spectroscopy(SC-XRD) and DFT studies. DFT-B3LYP optimized the molecular structures with a 6-311G (d, p) basis set to accomplish the global minimum energy state. 1H NMR confirmed the occurrence of H-bonding between the phenolic hydrogen and azomethine nitrogen in both molecules, further supported by SC-XRD analysis and DFT studies. The structural parameters such as bond angle, bond length, and dihedral angle derived from the optimized structure of molecules with C1 symmetry were compared with the corresponding parameters extracted from the ORTEP diagrams for both anils. Appreciable harmony of the structural parameters was achieved between these two analyses, confirming the anils’ purity. Slight discrepancy observed between DFT and SC-XRD analyses was attributed to the difference in the state of the molecules. Geometric optimization indicated the molecules to be coplanar. The MEP surface and atomic charges on the atoms envisaged the electron population and charged sites of the anils. Conclusively, both the anils have a suitable structural hierarchy for superior electron transport from the phenyl rings over the entire molecular framework suitable for optoelectronics applications.