Structural-property relationship in halogen-bonded Schiff base derivative: Crystal structure, computational and SARS-CoV-2 docking studies

We synthesized the halogenated Schiff base compound to understand the influence of halogen and
hydrogen bonding interactions. The Schiff base compound is characterized by FTIR, SEM-EDAX and
single-crystal X-ray diffraction studies. The structural studies reveal that the 4-chloro-2-(((4-chlorobenzyl)
imino) methyl) phenol crystallizes in the monoclinic, P21 /n space group. The O1-H1···N1 strong hydrogen
bond forms the intramolecular pseudo chelating ring motif and acts as a coordinating site for metal com-
plexes. The intra, intermolecular and π···π interactions were involved in the construction of supramolec-
ular architecture. The interesting type-I halogen bonds having trans geometry are exhibited. Hirshfeld
surface analysis supports the interactions observed in the crystal structure, and the energy framework
analysis provides the stabilization interaction energy among the molecular pairs. The enrichment ratio
provides favored contacts between the atomic pair and gives strong validation to the halogen···halogen
and halogen···hydrogen bonds. The DFT studies give more insight into electronic structure and provide a
global and local parameter of the molecule. NBO studies provide stabilization energy and charge transfer
within the molecule. The QTAIM studies were used to calculate the strength of the halogen, hydrogen
and stacking intermolecular interaction. Further, docking studies were carried out for COVID-19 proteins
to reveal the structural-function properties of halogen and hydrogen bonds present in the synthesized
compound.