Preparation and characterization of N,N-diacetatodithiocarbamato metal complexes with large negative charges

Dithiocarbamatocarboxylate (DTCC) Ligands-Building Blocks for Hard/Soft-Heterobimetallic Coordination Polymers

Four zinc/platinum(II) heterobimetallic coordination polymers with dithiocarboxylate-functionalized carboxylate (DTCC) ligands were prepared by different synthetic approaches and characterized by elemental analyses, IR and NMR (¹H, ¹³C, and ¹⁹⁵Pt) spectroscopy, thermal analyses coupled with mass spectrometry (TG/DTA/MS), and single-crystal and powder X-ray diffraction studies. Sequential syntheses via the carboxylic acid substituted platinum dithiocarbamates and zinc acetate revealed crystalline products in good to excellent yields. One-pot preparations from potassium DTCC salts, K₂PtCl₄, and ZnCl₂ led to comparable products, thus demonstrating the high selectivity of the two donor groups toward platinum(II) and zinc. [SSC-N(Me)CH₂COO]^2- and [SSC-N(CH₂COO)(CH₂COOH)]^2-, DTCC ligands derived from sarcosine and iminodiacetic acid, respectively, were found to form planar zigzag chains with zinc and platinum(II) ions, while the use of the l-proline-derived ligand [SSC-NC₄H₇COO]^2- results in a helical structure. In the case of [SSC-N(CH₂COO)₂]^3-, two-dimensional arrays are formed. All compounds are thermally stable up to 240-400 °C under nitrogen.