title: Unexpected formation of novel organometallic hetero-cation crystals with a rare coordination mode.
abstract: The imitative synthesis of the ionic liquid [bmim][Co(CO)(4)], carried out in organic solvents instead of water, produced an unexpected liquid complex with partial crystallization. The resulting solid was confirmed to be the novel hetero-cation salt, [bmim]K[Co(CO)(4)](2) () and a crystallographic investigation revealed an extremely unusual (CO)(7)-K coordination mode. When the organic cation was replaced by [C(4)Py](+), similar crystallization was also obtained, forming [C(4)Py]K[Co(CO)(4)](2) (), which has an analogous structure. Both of these cases indicate an interesting influence that these organic cations have on the crystallization of organometallic structures that yields new structural examples.
authors.affiliation: State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Fan-Guo
authors.initials: FG
authors.lastname: Deng
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Chun-Gu
authors.initials: CG
authors.lastname: Xia