Rapid microwave synthesis of tetrahedral pyrazole/Co(II) complex: [N[sbnd]H···Cl] synthon, XRD/HSA-interactions, DFT/TD-DFT, physiochemical, antifungal, antibacterial, and POM bio-calculations

Abstract

A new coordination complex, CoCl2(NNH)2, was synthesized by complexation of the pyrazole (NNH) ligand with CoCl2 in less than 5 min with a high yield (>85%). The synthesis was done using microwave radiation in water solvent where no side products were detected. The complexation was confirmed using UV–visible, CHN-analysis, and FT-IR analysis and compared to theoretical IR, DFT and TD-DFT calculations. CoCl2(NNH)2 crystallizes in a C2/c space group with distorted tetrahedral center as shown by single-crystal X-ray diffraction, two types of heteromeric [NH···Cl] synthons have been recorded, such interactions type and ratios were confirmed also via Hirsfield surface analysis (HSA). The desired complex was evaluated for its antibacterial activity against four classes of gram-positive and gram-negative bacteria, and its antifungal activity against four types of fungi. The complex's physio-chemical properties, toxicity risk, lipophilicity, and pharmacophore sites were studied using the POM (Petra-Osiris-Molinspiration) bio-computational theory.