Platinum(II) and palladium(II) thiolate complexes; synthesis, characterization, crystal structure, DFT, Hirshfeld surface analysis and anticancer studies

Abstract

The synthesis and characterization of platinum(II) and palladium(II) mixed ligand complexes, [M(mtzS)2(dppm)] (M = Pt or Pd), have been described. These complexes were synthesized through a one-pot reaction involving K2MCl4, KmtzS (prepared from HmtzS and KOH), and dppm. The prepared complexes 1 and 2 have been characterized by using various analytical techniques including conductivity measurements, IR spectroscopy, UV-Vis spectroscopy, 31P and 1H NMR spectroscopy and 1 by X-ray crystallographic studies. The in vitro anti-cancer activity of complexes 1 and 2 against breast cancer cells (MCF7 cell line), was evaluated using the MTT assay showed a moderate activity with an IC50 value of 27.59 µg/ml for 1 and 28.82 µg/ml for 2. Additionally, the ligands and complexes underwent full geometry optimization using density functional theory (DFT). The calculated geometric and spectral data were found to be in good agreement with the experimental results. Theoretical calculations of molecular orbitals (HOMO-LUMO) and their energies suggested the occurrence of charge transfer within the complexes. KEY WORDS: Platinum(II), Palladium(II), Thiolate, Diphosphine, X-ray crystallography Bull. Chem. Soc. Ethiop. 2024, 38(5), 1261-1273.                                                  DOI: https://dx.doi.org/10.4314/bcse.v38i5.6