A study of zinc complexes of the metalloligand [Pt₂(μ-S)₂(PPh₃)₄] of the type [Pt₂(μ-S)₂(PPh₃)₄ZnL]⁺ (L = bidentate chelating ligand)

Abstract

Reactions of [Pt₂(μ-S)₂(PPh₃)₄] with zinc acetate and an ancillary chelating ligand L (HL = 8-hydroxyquinoline, 8-tosylaminoquinoline or maltol) with added trimethylamine in methanol give new cationic platinum–zinc sulfide aggregates [Pt₂(μ-S)₂(PPh₃)₄ZnL]⁺, isolated as their BF₄⁻ salts. The complexes were characterized by NMR spectroscopy, ESI mass spectrometry, microelemental analysis, and an X-ray structure determination of the tosylamidoquinoline derivative [Pt₂(μ-S)₂(PPh₃)₄Zn(TAQ)]BF₄, which showed a distorted tetrahedral coordination geometry at zinc. Additional examples, containing picolinate, dithiocarbamate, or dithiophosphinate ligands were also synthesized and partly characterized in order to demonstrate a wider range of available derivatives.

Keywords:

• Platinum complexes
• Zinc complexes
• Sulfide ligand
• Metalloligand
• Crystal structure
• Electrospray ionization mass spectrometry

Acknowledgments

We thank the University of Waikato for financial support of this work, Pat Gread and Wendy Jackson for mass spectrometry assistance and technical support, and Dr Tania Groutso (University of Auckland) for collection of the X-ray data-set. WH thanks Professor Paul Low (University of Durham, UK) for provision of facilities for the writing of this manuscript.