A novel azide copper complex: [[Azido{bis[2-(piperidin-1-ylmethyl)pyridine]}copper(II)]perchlorate] hydrate

Synthesis and single crystal X-ray diffraction study were carried for compound {[Cu(C₁₁H₁₆N₄)₂(N₃)](ClO₄)} · H₂O (I). The structure is molecular, and the Cu²⁺ ion is in a five-coordinated compressed trigonal bipyramid environment. Copper ion is bound to five N atoms, in which four N atoms are from two chlelating ligands 2-(piperidin-1-ylmethyl)pyridine and the fifth N donor is from a monodentate azido ligand. The complex cations [Cu(C₁₁H₁₆N₄)₂(N₃)]⁺, the perchlorate anions, and solvent water molecules are further joined into three dimensional supramolecular networks by rich hydrogen bonds including strong O-H…N between solvent water and azide ion and O-H…O between solvent water and perchlorate ion, and weak hydrogen bonds C-H…O, and weak bifurcated hydrogen bonds C-H/C-H…N in which N atom of azide ion serving as bifurcated acceptor and two C-H groups as donors.     

Crystal structure of copper(II) bis-hexafluoroacetylacetonate

An X-ray diffraction investigation has performed for copper(II) bis-hexafluoroacetylacetonate (Bruker AXS P4 automatic diffractometer, MoK radiation, t = –25°C). Crystal data for C₁₀H₂CuF₁₂O₄: a = 5.530(1) Å, b = 6.038(1) Å, c = 11.266(2) Å, = 95.948(3)°, = 101.743(3)°, = 92.298(3)°, space group; P1, V = 365.6(1) ų, Z = 1, d _calc = 2.169 g/cm³. The square-planar environment of the copper atom (Cu-O_av 1.912 Å, O-Cu-O_av 93°) is completed to bipyramidal by two fluorine atoms of the neighboring molecules, Cu...F 2.71 Å and 2.75 Å.Original Russian Text Copyright © 2004 by S. A. Gromilov, I. A. Baidina, P. A. Stabnikov, and G. V. RomanenkoTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 502–507, May–June 2004.     

Crystal structure of monoaquatetra(3,5-dimethylpyrazole)copper(II) nitrate [Cu(C5H8N2)4(H2O)](NO3)2

The crystal structure of monoaquatetra(3,5-dimethylpyrazole)copper(II) nitrate [Cu(C₅H₈N₂)₄(H₂O)]×(NO₃)₂ is determined (Syntex P2₁ automated diffractometer, θ/2θ scan mode within the 2θ range 3–55° at a variable rate, V_min=5 deg/min, λMoK_α graphite monochromator, 5170/2349 measured/observed I_hk1, absorption taken into account experimentally, R_aniso=0.069). The parameters of the monoclinic unit cell are as follows: a=23.569(4), b=8.177(2), c=17.250(6) Å, β=121.65(2)°, V=2830(2) ų, Z=4C₂₀H₃₄CuN₁₀O₇, d_calc=1.388 g/cm³. The space group P2₁ was chosen by the process of structure solution and refinement. The structure is of island type. The complex cations [CuL₄(H₂O)]²⁺ and the (NO₃)^? anions form mixed layers in the planes parallel to (010) at y?0.36 and 0.87. The central atoms of two crystallographically independent complex cations [CuL₄(H₂O)]²⁺ are surrounded with five atoms (O_{H 2 O}+4N) with average Cu?O_{H 2 O} and Cu?N distances of 2.23(2) and 2.04(4), respectively, which form distorted trigonal bipyramids. The average bond lengths in the pyrazole rings are the following: N?N=1.40, N?C=1.40, (C?C)_ring=1.42, and C_ring?C_Me=1.50 Å.     

Crystal structure of [2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine]-(azido)(chloro)copper(II).

In the title compound, the coordination around the Cu atom is a distorted square-pyramid involving three N atoms from the ligand and one N atom from the azido group at the basal plane. The Cl atom is located at the apical position. The Cu atom is 0.32(5)A above the basal plane. There are three intramolecular and four weak intermolecular hydrogen bonds in the structure. IR spectra confirm the asymmetric N3 stretching vibrations of the terminal azide group.     

Synthesis and electrochemistry of M(II) N2O2 schiff base complexes: X-Ray structure of {Ni[Bis(3-chloroacetylacetone)ethylenediimine]}

The synthesis and characterization of [Ni(BCE)] and [Cu(BCE)] (where BCE = bis(3-chloroacetylacetone)ethylenediimine) are described. The coordination geometry of [Ni(BCE)] was determined by X-ray crystallography. It was found to be planar and four coordinate in the solid state. The electrochemical properties of M(Chel), where M = Co(II), Ni(II) and Cu(II), and Chel = BAE (bis(acetylacetone)ethylenediimine), BBE = bis(benzoylacetone)ethylenediimine, BFE (bis(1,1,1-triflouroacetylacetone) ethylenediimine and BCE ligands were investigated in DMF and DMSO as solvents. The oxidation potentials changed from left to right in the periodic table in the trend: Co < Ni < Cu, while the reduction potentials changed according to the trend: Ni > Co > Cu. The oxidation potentials of M(II) to M(III) (M = Ni and Cu) increased according to the Schiff base ligands in the trend: BAE < BBE < BCE < BFE, while the reduction potentials followed a reverse trend: BAE > BBE > BCE > BFE. The oxidation potentials of M(II) to M(III) increased according to the solvent in the trend: DMSO < DMF.     

Crystal structure of bis(l-arginine)copper(II) hexachlorodimercurate, [Cu(l-Arg)2]Hg2Cl6

By means of X-ray diffraction the chain structure of [Cu(l-Arg)₂]Hg₂Cl₆ (monoclinic, a = 10.2348(9) Å, b = 9.1386(7) Å, c = 14.8521(14) Å, β = 97.455(11)°, space group P2₁) is established. The chains are formed by square-planar [Cu(l-Arg)₂]²⁺ cations of the type trans-[Cu(N)₂(O)₂] (l-Arg is the zwitter-ion of arginine; Cu-N 1.992 Å and 1.938(6) Å, Cu-O 1.953 Å and 1.967(4) Å) that are bonded to two adjacent binuclear [Cl₂Hg(μ-Cl)₂HgCl₂]^2? ions through its clorine atoms Cl (Hg-Cl bonds are within 2.34–2.78 Å). With these two additional Cu…Cl contacts Cu adopts the geometry of an elongated octahedron with two apical Cl (Cu-Cl 2.961 Å and 3.064(3) Å).