Hydrogen-Bonded Networks Based on Cobalt(II), Nickel(II), and Zinc(II) Complexes of N,N'-Diethylurea

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 ⋯ O(DEU) hydrogen bonds. The [M(DEU)6]2+ cations and counterions self-assemble to form hydrogen-bonded 2D architectures in 2–4 that conform to 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)

Hydrogen-Bonded Networks Based on Cobalt(II), Nickel(II), and Zinc(II) Complexes of N,N-Diethylurea

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)

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 CoI2 in EtOH yielded the “clathrate-coordination” compound [CoU6]I2·4U (1). The complex crystallizes in the monoclinic space group P21/c. The lattice constants are a = 9.844(4), b = 7.268(3), c = 24.12(1) Å, and β=98.12(1)∘. The crystal structure determination demonstrates the existence of octahedral [CoU6]2+ cations, I- counterions, and two different types (two U1 and two U2) of hydrogen-bonded, lattice urea molecules. The [CoU6]2+ cations and the U1 lattice molecules form two-dimensional hydrogen-bonded layers which are parallel to the ab plane. The I- anions are placed above and below each layer, and are hydrogen bonded both to U1 molecules and [CoU6]2+ cations. Each U2 molecule is connected to a [CoU6]2+ cation through an N–H⋯O hydrogen bond resulting in a three-dimensional network. Room temperature magnetic susceptibility and spectroscopic (solid-state UV/Vis, IR, Raman) data of 1 are discussed in terms of the nature of bonding and the known structure

Hydrogen-bonded networks based on manganese(II), nickel(II), copper(II) and zinc(II) complexes of N,N′-dimethylurea

A project related to the crystal engineering of hydrogen-bonded coordination complexes has been initiatied and some of our first results are presented here. The compounds [Mn(DMU)(6)](ClO4)(2) (1), [Ni(DMU)(6)](ClO4)(2) (2), [Cu(OClO3)(2)(DMU)(4)] (3) and [Zn(DMU)(6)](ClO4)(2) (4) have all been prepared from the reaction of N, N’-dimethylurea (DMU) and the appropriate hydrated metal perchlorate salt. Crystal structure determinations of the four compounds demonstrate the existence of [M(DMU)(6)](2+) cations and ClO4- counterions in (1), (2) and (4), whereas in (3) monodentate coordination of the perchlorate groups leads to molecules. The [ M( DMU)(6)](2+) cations and ClO4- anions self-assemble to form a hydrogen-bonded one-dimensional (1D) architecture in (1) and different 2D hydrogen-bonded networks in (2) and (4). The hydrogen bonding functionalities on the molecules of (3) create a 2D structure. The complexes were also characterised by room-temperature effective magnetic moments and i.r. studies. The data are discussed in terms of the nature of bonding and the known structures