Platinum and palladium complexes of thiosemicarbazones derived of 2-acetylthiophene: Synthesis and spectral studies

The reaction of 2-acetylthiophene thiosemicarbazone (2-HATT) and 2-acetylthiophene 4-phenylthiosemicarbazone (2-HAT-4-FT) with Pd(COD)Cl2 (COD = 1,5-cyclooctadiene) and trans-Pt2PEt3Cl4 yielded four new metal complexes: [Pd(2-HATT)Cl2] (1), [Pd(2-ATT)2] (2), [Pd(2-AT-4-FT)Cl] (3) and [Pt(2-ATT)(PEt3)Cl] (4). Apart from compound 3 all the others were characterised by 1H and 13C{1H} NMR, infrared spectroscopy, and elemental analysis. Multinuclear NMR experiments of 31P{1H} and 195Pt{1H} of complex 4 have revealed that the ligand 2-HATT behaves as a bidentate chelating agent towards Pd(COD)Cl2 and trans-Pt2PEt3Cl4 whereas ligand 2-HAT-4-FT forms a tridentate chelating complex with Pd(COD)Cl2.