Octahedral and Tetrahedral Cobalt(II) Sites in Cobalt Chloride Complexes with Polyethers

A reaction of cobalt chloride hexahydrate with dimethoxyethane (dme) resulted in a dinuclear complex [CoCl2(dme)](2) (1). The complex 1 reacted with di(2-methoxyethyl) ether (diglyme) in tetrahydrofuran (thf) solvent achieving polymeric [Co2Cl4(diglyme)](n) (2). A reaction of cobalt chloride hexahydrate, diglyme and (CH3)(3)SiCl in thf yielded the crystals of [Co2Cl4(diglyme)(thf)] (3). Both, tetrahedral and octahedral environments of cobalt ions were found in each of the complexes, 1, 2 and 3. Cobalt ions display a distorted octahedral geometry with bridging chlorides and terminal oxygen atoms from ether ligands and a distorted tetrahedral geometry with non-bridging and bridging chlorides. A four- and a six-coordinate cobalt ion are linked by a double chloride bridge in the dinuclear complexes 1 and 3. Two tetrahedral or two octahedral cobalt ions in 2 are connected by double chloride bridges in dinuclear units which are linked to infinite chains by single chloride bridges. (doi: 10.5562/cca1747)