(E)-2-[(4-Chlorophenyl)iminomethyl]-5-methoxyphenol and (E)-2-[(2-chlorophenyl)iminomethyl]-5-methoxyphenol: X-ray and DFT-calculated structures

Abstract

The crystal structures of the title 4-chlorophenyl, (I), and 2-chlorophenyl, (II), compounds, both C14H12ClNO2, have been determined using X-ray diffraction techniques and the molecular structures have also been optimized at the B3LYP/6-31 G(d, p) level using density functional theory (DFT). The X-ray study shows that the title compounds both have strong intramolecular O-H center dot center dot center dot N hydrogen bonds and that the crystal networks are primarily determined by weak C-H center dot center dot center dot pi and van der Waals interactions. The strong intramolecular O-H center dot center dot center dot N hydrogen bond is evidence of the preference for the phenol-imine tautomeric form in the solid state. The IR spectra of the compounds were recorded experimentally and also calculated for comparison. The results from both the experiment and theoretical calculations are compared in this study.