Synthesis and structures of dinuclear palladium complexes with 1,3-benzimidazolidine-2-thione and 1,3-imidazoline-2-thione

Acta Crystallogr E Crystallogr Commun. 2023 Jan 10;79(Pt 2):79-84. doi: 10.1107/S2056989023000166. eCollection 2023 Jan 1.

Abstract

The synthesis and structures of dinuclear palladium complexes with 1,3-benz-imidazolidine-2-thione (bzimtH) and 1,3-imidazoline-2-thione (imtH) are reported, namely, bis-(μ-1H-benzimidazole-2-thiol-ato)-κ2 N 3:S2 S:N 3-bis-[cyanido(tri-phenyl-phosphine-κP)palladium(II)], [Pd2(C7H5N2S)2(CN)2(C18H15P)2] or [Pd2(μ-N,S-bzimtH)2(CN)2(PPh3)2] (1), and bis-(μ-1H-imidazole-2-thiol-ato)-κ2 N 3:S2 S:N 3-bis-[cyanido(tri-phenyl-phosphine-κP)palladium(II)] aceto-nitrile 0.58-solvate, [Pd2(C3H3N2S)2(CN)2(C18H15P)2]·0.58C2H3N or [Pd2(μ-N,S-imtH)2(CN)2(PPh3)2]·0.58C2H3N (2). The compound [Pd2(μ-N,S-bzimtH)2(CN)2(PPh3)2] is located on a crystallographic twofold axis while [Pd2(μ-N,S-imtH)2(CN)2(PPh3)2]. 0.58(C2H3N) contains two partially occupied aceto-nitrile solvent mol-ecules with occupancies of 0.25 and 0.33. In both of these compounds, the anionic bzimtH- and imtH- ligands coordinate through N,S-donor atoms in a bridging mode, covering four coordination sites of two metal centers and other two sites are occupied by two PPh3 ligand mol-ecules. Finally, the remaining two sites of two metal centers are occupied by cyano groups, abstracted by the metals from the solvent during reaction. In the packing of the 1,3-benzimidazolidine- 2-thione and 1,3-imidazoline-2-thione complexes, there are intra-molecular π-π inter-actions involving the thione moiety as well as an N-H⋯N hydrogen bond linking the thione and cyano ligands. In addition, in 2, as well as the π-π inter-action involving the thione moieties, there is an additional π-π inter-action involving one of the thione moieties and an adjacent phenyl ring from the tri-phenyl-phosphine ligand. There are also C-H⋯N inter-actions between the imidazoline rings and the aceto-nitrile N atoms.

Keywords: benzimidazolidine- 2-thione complexes; crystal structure; dinuclear palladium complexes; imidazoline-2-thione complexes.

Grants and funding

JPJ acknowledges the NSF–MRI program (Grant No. CHE-1039027) for funds to purchase an X-ray diffractometer. MZ acknowledges the NSF Grant CHE 0087210, Ohio Board of Regents Grant CAP-491, and Youngstown State University for funds to purchase an X-ray diffractometer.