Palladium and platinum complexes of primary 2-pyridinethioamide

Abstract

Primary thioamide, 2-pyridinethioamide reacts with palladium and platinum compounds K2PdCl4, K2PtCl4 and Pd(CH3COO)2 to give the products [PdCl2(2-pyridinethioamide)].2DMF (1), [PtCl2(2-pyridinethioamide)] (2a), [Pd(2-pyridinethioamide)2]Cl2 (3), [Pt(2-pyridinethioamide)2]Cl2 (4) and [Pd(2-pyridinethioamidinate)2] (5), respectively. The structures 1, [PtCl(DMSO)(2-pyridinethioamidinate)] (2b), which was obtained from crystallization of 2a in DMSO, 4 and 5 were determined by X-ray crystallography. Compound 3 was spectroscopically analyzed and found to have a structure similar to that of 4. The ligand coordinates in a neutral form in complexes 1, 2a, 3 and 4, but in 2b and 5 it exists in a deprotonated form. Compounds 3 and 4 are cationic complexes with Cl− counterions in the structure. The ligand prefers coordination as the bidentate N(py),S-mode in all the crystallized compounds. In the bis-chelates, the sulfur and the nitrogen atoms are mutually trans-located. Computational DFT calculations and topological charge density analysis were utilized to clarify the coordination modes and to interpret the spectral information.