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Updated: May 20, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
([2.2.2]Cryptand-κ(6)O)potassium (η(4)-cyclo-octa-diene)bis-(η(2)-pyrene)cobaltate(1-) pentane hemisolvate
William W Brennessel1, John E Ellis
1Department of Chemistry, 207 Pleasant Street SE, University of Minnesota, Minneapolis, MN 55455, USA.
Abstract:
The cation, anion, and solvent in the title compound, [K(C(18)H(36)N(2)O(6))][Co(C(8)H(12))(C(16)H(10))(2)]·0.5C(5)H(12), are well separated. The pentane solvent mol-ecules are found in channels along [100] and were modeled as disordered over crystallographic inversion centers. Using the mid-points of the coordinated olefins, the angle between the C(py)/C(py)-Co-C(py)/C(py) and the C(cod)/C(cod)-Co-C(cod)/C(cod) planes (py is pyrene and cod is cyclo-octa-diene) is 67.6 (2)°. Thus, the overall geometry of the coordination sphere around cobalt is best described as distorted tetra-hedral.
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