Studies of pendant-arm macrocyclic ligands. Part 1. Synthesis of two new penta-aza ligands, and observation of pH-dependent reversible equilibria between trigonal-bipyramidal and square-planar forms of their nickel(II) and copper(II) complexes. Crystal structure of a trigonal-bipyramidal nickel(II) complex

1984 ◽  
pp. 1937 ◽  
Author(s):  
Nathaniel W. Alcock ◽  
Robert G. Kingston ◽  
Peter Moore ◽  
Colin Pierpoint
Keyword(s):  
Crystal Structure ◽  
Macrocyclic Ligands ◽  
Trigonal Bipyramidal ◽  
Pendant Arm ◽  
Square Planar ◽  
Ph Dependent

Platinum(II) Template Synthesis of a Pendant-Arm Macrocycle

1998 ◽  
Vol 51 (9) ◽  
pp. 871 ◽  
Author(s):  
Hong Xiao ◽  
Geoffrey A. Lawrance ◽  
Trevor W. Hambley
Keyword(s):  
Crystal Structure ◽  
Template Synthesis ◽  
Crystal Structure Analysis ◽  
Macrocyclic Complex ◽  
Triclinic Space Group ◽  
X Ray ◽  
Pendant Arm ◽  
Major Isomer ◽  
Square Planar ◽  
R Value

Platinum(II)-directed condensation of ethane-1,2-diamine with nitroethane and formaldehyde yields the colourless macrocyclic complex (trans-6,13-dimethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecane)plat- inum(II), [Pt(1)]2+, in good yield. This parallels chemistry reported earlier around other triad members nickel(II) and palladium(II). The pendant nitro groups in the major isomer are disposed on opposite sides of the macrocycle in a trans geometry, as confirmed by the X-ray crystal structure analysis of [Pt(1)] (ClO4)2, which crystallizes in the triclinic space group P-1, a 8·041(4), b 8·482(4), c 9·443(3) Å, α 69·44(3), β 67·66(4), γ 71·73(4)°,Z1, and was refined to an R value of 0·027 on 1920 F. The platinum ion lies in a square planar environment of four nitrogen donors, with typical Pt–N distances; comparisons between the platinum(II) and palladium(II) complexes of (1) and its analogue (2), with diammonio groups in place of dinitro groups, are discussed

Preparation and structure of chloro-copper(II) complexes of 7-azaindole

1992 ◽  
Vol 70 (12) ◽  
pp. 2846-2855 ◽  
Author(s):  
Jacques Poitras ◽  
André L. Beauchamp
Keyword(s):  
Crystal Structure ◽  
Infrared Spectrum ◽  
Membered Ring ◽  
Tetranuclear Cluster ◽  
Trigonal Bipyramidal ◽  
Square Planar ◽  
Rich Solution ◽  
Deep Green ◽  
Light Green ◽  
Oxide Ion

The light green trans-CuCl2(Haza)2 adduct precipitates immediately from mixtures of CuCl2•2H2O with excess 7-azaindole (Haza) in methanol. Upon standing in azaindole-rich solution, this solid is replaced by a deep green Cu2Cl4(Haza)6 compound, whose crystal structure (orthorbombic, Fdd2, a = 26.558, b = 23.750, c = 12.727 Ǻ, Z = 8, R = 0.068, Rw = 0.066) shows the presence of square-planar [Cu(Haza)4]2+ and trans-[CuCl2(Haza)2] units connected by bridging Cl− ions, making each Cu atom (4 + 2)-coordinated. Azaindole is bonded to the metal via the pyridine N7 site, whereas the five-membered ring retains its N1—H proton. The azaindole ligands are disordered over two orientations in the [CuCl2(Haza)2] unit. The square-planar Cu species and apical Cl− ions lie on a twofold axis and define along c an infinite chain based on the [Formula: see text] pattern. Equimolar mixtures of azaindole and CuCl2•2H2O yield a brown Cu4OCl6(Haza)4 compound. The crystal structure of its ethyl acetate solvate (monoclinic, P21/c, a = 11.661, b = 22.415, c = 15.077 Ǻ, β = 109.85°, Z = 4, R = 0.048, Rw = 0.054) shows the presence of a tetranuclear cluster consisting of a μ4-oxide ion surrounded by a tetrahedron of Cu(II) atoms bridged in pairs by chlorine atoms. The trigonal-bipyramidal coordination of each copper atom is completed by a monodentate N7-bonded azaindole molecule hydrogen bonded to bridging chlorines via N1—H. The influence of complexation on the infrared spectrum of azaindole is discussed.

Synthesis, Crystal Structure And Spectroscopic Studies Of A Mixed Ligand Copper (Ii) Complex: Trans-Bis(Succinimidato)-Bis(Benzylamino)Cu(Ii)

2006 ◽  
Vol 61 (8) ◽  
pp. 979-982 ◽  
Author(s):  
Murat Taş ◽  
Hanife Saraçoğlu ◽  
Hümeyra Bati ◽  
Nezihe Çalışkan ◽  
Orhan Büyükgüngör
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Spectroscopic Studies ◽  
Mixed Ligand ◽  
Interplanar Angle ◽  
Space Group ◽  
Square Planar

The molecules of the title compound, [Cu(C11H13N2O2)2], lie across centres of inversion in space group P21/c and are linked by intermolecular N-H···O and C-H···O hydrogen bonds. The central Cu atom has a slightly distorted square-planar coordination comprised of four N atoms. Cu-N bond distances are 1.975(2) and 2.020(2) Å . The interplanar angle between the phenyl and succinimidato ring is 87.34(10)°

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