Synthesis, X-Ray Structure, and Characterization of a Complex Containing the Hexakis(urea)cobalt(II) Cation and Lattice Urea Molecules
The 12: 1 reaction of urea (U) with CoI2in EtOH yielded the “clathrate-coordination” compound[CoU6]I2·4U (1). The complex crystallizes in the monoclinic space group P21/c. The lattice constants area= 9.844(4),b= 7.268(3),c= 24.12(1) Å, andβ=98.12(1)∘. The crystal structure determination demonstrates the existence of octahedral[CoU6]2+cations,I-counterions, and two different types (twoU1and twoU2) of hydrogen-bonded, lattice urea molecules. The[CoU6]2+cations and theU1lattice molecules form two-dimensional hydrogen-bonded layers which are parallel to theabplane. TheI-anions are placed above and below each layer, and are hydrogen bonded both toU1molecules and[CoU6]2+cations. EachU2molecule is connected to a[CoU6]2+cation through anN–H⋯Ohydrogen bond resulting in a three-dimensional network. Room temperature magnetic susceptibility and spectroscopic (solid-state UV/Vis, IR, Raman) data of1are discussed in terms of the nature of bonding and the known structure.