Crystal Structures and Selected Properties of CoII Containing Thiostannates prepared by a New Room Temperature Route

Abstract

The room temperature reaction of Na4Sn2S6·5H2O with CoCl2·6H2O and 2‐(aminomethyl)pyridine (2‐AMP) or trans‐1,2‐diamino‐cyclohexane (DACH) leads to crystallization of two compounds with the compositions [Co(2‐(aminomethyl)pyridine)3]2 Sn2S6·10H2O (1) and [Co(trans‐1,2‐diaminocyclohexane)3]2Sn2S6·8H2O (2). In both compounds [Sn2S6]4– anions are present that are charge balanced each by two Co2+ centered complexes. Each of the two CoII cations are sixfold coordinated by six N atoms of three 2‐AMP or DACH ligands within slightly distorted octahedra. In compound 1, the two complexes are linked by one [Sn2S6]4– anion via strong N–H···S hydrogen bonds into centrosymmetric charge neutral trimeric units, that are further linked by weak C–H···S and N–H···S hydrogen bonds into chains that are directed along the a axis. These chains are further joined by N–H···O and O–H···O hydrogen bonds into a 3D network, with the H2O molecules forming chains along the b axis. The crystal structure of 2 is similar to that of 1 featuring trimeric units which are also linked into chains. Between the chains water molecules are embedded that link the chains into a 3D network. Upon heating 2 in a thermobalance the water and ligand molecules are removed in discrete steps, indicating that compounds with more condensed thiostannate networks will form.