Synthesis, crystal structure, and properties of the adduct of bis(O,O′-diisopropyl dithiophosphato)nickel(II) with pyridine [Ni(i-Pr2dtp)2(py)2]

A new adduct bis(pyridine)-bis(O,O′-diisopropyl dithiophosphato-S,S′)nickel(II), [Ni(i-Pr2dtp)2(py)2] (dtp = dithiophosphate, py = pyridine) has been obtained by re-crystallization from CH3COCH3. The crystal and molecular structure of the title complex has been determined by X-ray crystallography. It crystallizes in the monoclinic system, space group P21/c, with lattice parameters a = 6.4890(13) Å, b = 16.386(3) Å, c = 14.830(3) Å, β = 99.74(3)°, V = 1554.1(5) Å3, and Z = 2. The crystal structure consists of discrete molecules of [Ni(i-Pr2dtp)2(py)2], which displays a slightly distorted octahedral geometry for the NiS4N2 chromophore. Two O,O′-diisopropyl dithiophosphate ions act as bidentate ligands with their S atoms coordinated to Ni atom. Each forms a four-membered chelate ring in the equatorial plane. The N atoms from two pyridine ligands are axially coordinated to the Ni atom. The Ni\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$---{\text{S}}$$ \end{document}S bond distances are 2.4492(8) Å and 2.5711(9) Å, and the Ni\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$---{\text{N}}$$ \end{document} bond distances are 2.127(3) Å. Thermal analyses show that the thermal decomposition of this adduct is so unstable that loss of two pyridine ligands begins at about 65°C. Electronic and IR spectra data is in agreement with the structural data.