Spectroscopic characterization, crystal structure determination, and solid-state assembly exploration using Hirshfeld surface analysis of 3-(2-methylphenyl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one and its Cd(II) phenanthroline complexes

Methyl anthranilate reaction was done with 2-methylphenyl isothiocyanate to synthesize the ligand 3-(2-methylphenyl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one HL which adopted thione tautomeric form. It was first converted into the respective sodium thiolate [C15H11N2OSNa] NaL, which was subsequently utilized in a reaction with cadmium chloride. This reaction resulted in the creation of complex I, which then reacted with o-phenanthroline to form complex [C42H30CdN6O2S2,2(C2H6O)] II. Crystal structure of the compounds HL and II was determined by single crystal XRD analysis. The asymmetric unit of HL composed of two molecules that were different relative to crystallography. The distinction between the molecules was characterized by the dihedral angle between 2-sulfanylidene-2,3-dihydroquinazolin-4(1H)-one and toluene in each molecule. In coordination sphere of cadmium complex II, bond lengths and bond angles indicated that highly distorted octahedral geometry was formed. The stabilization of the supramolecular assembly of both compounds was influenced by various intermolecular interactions, which were investigated through Hirshfeld surface analysis. Using NMR spectroscopy 1Н and 13C, the effect of increasing the temperature from 298 K to 343 K on chemical shifts, signal width and shape was studied for all the compounds obtained. © 2024 Elsevier B.V.