Formation of a solubilized cobalt block oligomer from a M2L-type double helicate.
The multi-dentate ligand, 2,3,5,6-tetrakis(2,2'-bipyridyl)pyrazine (L) and divalent cobalt self-assemble to a block co-polymer-like oligomer in solution, which contains at least the L(7)Co(8) fragment. The extent of oligomerization is sensitive to the water content in acetonitrile solution. In the solid state, the simple monomer [LCo(2)(CH(3)CN)(4)][ClO(4)](4) is isolated. The X-ray structure of the crystallized material (containing four CH(3)CN solvate molecules) reveals a double-helical complex with two heptadentate Co(II) sites, and a helical pitch of approximately 28.1 A. Coupled Co(I/II) redox processes are observed between the two metal centres.
Heirtzler
Fenton
F
Chemical Laboratory, University of Kent, Canterbury, Kent, UKCT2 7NJ.
Santi
Saverio
S
Howland
Kevin
K
Weyhermüller
Thomas
T
D001665:Binding Sites; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008968:Molecular Conformation; D011108:Polymers / Q000737:chemistry*; D012995:Solubility; D014867:Water
D011108:Polymers; D014867:Water; D003035:Cobalt