COMPLEXATION OF METAL-SALTS WITH MACROCYCLIC POLYETHERS IN APROTIC ORGANIC-SOLVENTS - CRYSTAL-STRUCTURE OF IONIC COMPLEXES [CO.15-CROWN-5.2CH3CN][COCL3.CH3CN]2.CH3CN, [CO.15-CROWN-5.2CH3CN][COCL4].CH3CN AND [CO.15-CROWN-5.2CH3CN][CO2CL6]

Interaction of anhydrous CoCl2 with 15-crown-5 in acetonitrile medium leads to the formation in solution and in the crystal of ionic compounds of three structural types: [Co.15-C-5.2AN][CoCl3.AN]2.AN, [Co.15-C-5.(AN)2][CoCl4].AN and [Co.15-C-5.(AN)2][Co2Cl6]. The complex formation has been studied by conductometric and spectrophotometric titration, but individual compounds by X-ray structural analysis. All three compounds were found to be the intracavital complexes. The cobalt polyhedron is a pentagonal bipyramid, the apical positions being occupied by nitrogens. Thermal decomposition of these compounds starts with the loss of acetonitrile, the final step being the destruction of the polyether ring.