Synthesis and Crystal Structure of Cobalt Complexes with Cucurbit[6]uril

Four cobalt complexes with cucurbit[6]uril (CB[6]), [Co(HO)](Bdc) · CB[6] · 14.5HO (I), 2(HNMe)[CoCl] · CB[6] ·12HO (II), [[Co(HO)Cl](CB[6])]Cl · 9HO (III) and [Co(HO)][Co(HO)(Dm)][CoCl] · CB[6] · 6HO (IV), were prepared by evaporation of the reaction solution containing cobalt chloride and cucurbit[6]uril (CB[6]). According to X-ray diffraction data, compound I is formed by packing of cationic cobalt aqua complexes, terephthalate anions, and CB[6] molecules linked together by hydrogen bonds with crystallization water molecules into a supramolecular cage. The structure of compound II represents a packing of CB[6] molecules, dimethylammonium cations, and anionic cobalt chloro complexes. Compound III contains tetranuclear cationic cobalt chloro aqua complexes with CB[6], with chloride anions acting as counter-ions. The crystal structure of IV is a packing of cationic cobalt aqua complexes, anionic cobalt chloro complexes, and CB[6] molecules linked by hydrogen bonds with crystallization water molecules into a supramolecular cage. The resulting compounds are characterized by IR spectra and elemental analysis data.