Abstract
Hexaamminecobalt(II) bis-[tetra-carbonyl-cobaltate(-I)], [Co(NH3)6][Co(CO)4]2, was synthesized by reaction of liquid ammonia with Co2(CO)8. The Co(II) atom is coordinated by six ammine ligands. The resulting polyhedron, the hexa-amminecobalt(II) cation, exhibits point group symmetry -3. The Co(-I) atom is coordinated by four carbonyl ligands, leading to a tetra-carbonyl-cobaltate(-I) anion in the shape of a slightly distorted tetra-hedron, with point group symmetry 3. The crystal structure is related to that of high-pressure BaC2 (space group R-3m), with the [Co(NH3)6](2+) cations replacing the Ba sites and the [Co(CO)4](-) anions replacing the C sites. N-H⋯O hydrogen bonds between cations and anions stabilize the structural set-up in the title compound.
Highlights
The reaction of dicobalt octacarbonyl with liquid ammonia has been known for several decades (Behrens & Wakamatsu, 1966)
The cobalt atom Co1 of the hexaamminecobalt(II) cation occupies Wyckoff position 3a with site symmetry 3. It is coordinated by six symmetry-related ammine ligands in form of a slightly distorted octahedron
Labelling of symmetryequivalent atoms has been omitted for clarity. doi:10.1107/S2056989015020290
Summary
Supporting information: this article has supporting information at journals.iucr.org/e. The reaction of Co2(CO) with bases has already been described in the literature (Hieber et al, 1960). The reaction of dicobalt octacarbonyl with liquid ammonia has been known for several decades (Behrens & Wakamatsu, 1966). [Co(NH3)6][Co(CO)4]2, which is obtained as orange air-sensitive crystals. During this reaction, CO is released and reacts with ammonia to urea. Structural data of of the title compound were missing and are presented in this communication
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Acta crystallographica. Section E, Crystallographic communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
