Vol. 6, Issue 2, Part B (2024)

This project details the synthesis and characterization of three complexes. The precursor ligand was synthesized by reacting 2-aminothiazole with phenyl isothiocyanate to get N-Phenyl-N-(2-thiazoyl) thiourea (PTTH²). Upon reacting the ligand with the [Pt(diphos)Cl₂] complex, the two thioamide protons were deprotonated, yielding complexes of the generic type [Pt(diphos) (PTT)]. Furthermore, the newly synthesized compounds were characterized using various spectroscopic techniques, including FT-IR and 1H-NMR. Both procedures validated the deprotonation of the two N-H protons. The FT-IR spectra indicated the existence of characteristic phosphine bands. Additionally, the ligand PTTH² and the complex [Pt(PPh₃)₂ (PTT)] were subjected to theoretical analysis, and their quantum parameters were assessed. The quantum calculations indicated that the Pt complexes possess a square planar shape with distorted angles.. Also, the 4d orbital of Pt(II) is highly diffused due to the interaction between the P, S, and N donor atoms with Pt ion. The HOMO and LUMO of PTTH² are spread among all atoms, having a HOMO-LUMO gap of 4.63 eV. The HOMO of [Pt(PPh₃)₂ (PTT)] is predominantly localized on nitrogen, sulfur, and certain benzene rings, whereas the LUMO is primarily associated with platinum and other benzene rings. The HOMO-LUMO gap is equal to 3.22 eV, which is near to some semiconductors such as TiO₂ anatase phase. Finally, the prepared complexes were tested against five bacterial species, and showed significant antibacterial action on most of them.