Τίτλος:
Hydrogen-Bonded Networks Based on Cobalt(II), Nickel(II), and Zinc(II) Complexes of N,N-Diethylurea
Περίληψη:
N,N’-diethylurea (DEU) was employed as a ligand to form the octahedral
complexes [M(DEU)(6)](2+) (M=Co, Ni and Zn). Compounds
[Co(DEU)(6)](BF4)(2) (1), [Co(DEU)(6)](CIO4)(2) (2),
[Ni(DEU)(6)](CIO4)(2) (3), and [Zn(DMU)(6)](CIO4)(2) (4) have been
prepared from the reactions of DEU and the appropriate hydrated
metal(II) salts in EtOH in the presence of 2,2-dimethoxypropane. Crystal
structure determinations demonstrate the existence of [M(DEU) 6] 2+
cations and CIO4- (in 2-4) or BF4- (in 1) counterions. The
[M(DEU)(6)](2+) cations in the solid state are stabilized by a
pseudochelate effect due to the existence of six strong intracationic
N-H center dot center dot center dot O-(DEU) hydrogen bonds. The
[M(DEU)(6)](2+) cations and counterions self-assemble to form
hydrogen-bonded 2D architectures in 2-4 that conformto the kgd (kagome
dual) network, and a 3D hydrogen-bonded rtl (rutile) network in 1. The
nature of the resulting supramolecular structures is influenced by the
nature of the counter-ion. The complexes were also characterized by
vibrational spectroscopy (IR).
