15061-57-1Relevant articles and documents
Structural studies on tris(2-cyanoethyl)phosphine complexes of Cu(I): The sensitivity of the secondary nitrile coordination to the nature of the anion
Davidson, Ross J.,Ainscough, Eric W.,Brodie, Andrew M.,Freeman, Graham H.,Jameson, Geoffrey B.
, p. 330 - 337 (2014)
Tris(2-cyanoethyl)phosphine (tcep) reacts with the copper(I) compounds, CuX (X = Cl, Br, I and SCN), in a 1:1 ratio to give 1:1 complexes, CuX(tcep), whereas it reacts with CuY (Y = PF6, ClO4, NO3, BH4, CN and CF3COO) in a 2:1 ratio to give the 2:1 complexes, CuY(tcep)2. Single crystal X-ray structures show that for the anions X = Br and SCN, the complexes are coordination polymers, [CuX(tcep)]n, with the Cu centres being bridged by the anion, and as well, one nitrile arm per tcep ligand coordinates intermolecularly to the Cu to give tetrahedral 'PBr2N' and 'PSN2' coordination spheres respectively. The 2:1 compounds exhibit a variety of structures. For Y = ClO4, CN and CF3COO polymeric structures are formed except for Y = BH4 where the compound is a discrete monomer, [Cu(BH 4)(tcep)2], with a chelating anion and two monodentate P-bound tcep ligands. Both the compounds obtained with Y = CN and CF 3COO also contain coordinated anions and are formulated as [Cu(CN)(tcep)2]n and [Cu(CF3COO)(tcep) 2]n respectively. In the case of Y = CN the anion is bridging and the tcep ligands are only P-bound giving a 'P2NC' coordination sphere. In contrast, for Y = CF3COO, the anion is an O-bound monodentate and the tcep ligands bridge to give a 'P2NO' environment for the copper. In the case of Y = ClO4, the anion is not coordinated but a polymeric structure, [Cu(tcep)2] n(ClO4)n, is formed via bridging tcep ligands linking Cu centres intermolecularly resulting in a 'P2N2' coordination sphere.
Gomberg, M.
, p. 398 - 398 (1923)
Preparations and properties of transition-metal pterin complexes. Models for the metal site in phenylalanine hydroxylase
Perkinson, Joanna,Brodie, Sharon,Yoon, Keum,Mosny, Karoline,Carroll, Patrick J.,Vance Morgan,Nieter Burgmayer, Sharon J.
, p. 719 - 727 (2008/10/08)
Syntheses and physical properties of pterin and pteridine complexes of first-row transition metals are described. Characterization used single-crystal x-ray diffraction, spectroscopic, and microanalytical methods. These data all indicate that pterin and pteridine ligands chelate via oxygen and nitrogen atoms. Three copper complexes have been structurally determined. Cu(tppb)(pterin) (1) [tppb- = tris(3-phenylpyrazolyl)hydroborate] crystallizes in the triclinic space group P1 with cell dimensions a = 11.835 (2) ?, b = 12.062 (2) ?, c = 12.831 (2) ?, α = 66.91 (1)°, β = 83.68 (1)°, and γ = 77.10 (1)° defining a volume of 1641.9 ?3 for Z = 2. The five-coordinate cupric ion has a square-pyramidal geometry, and the pterin ligand occupies two equatorial positions. Pterin coordination in 1 significantly differs from the only extant report of a cupric pterin complex both in orientation and in Cu-O bond strength. Cu(ethp)2(phen) (4) [ethp = 2-(ethylthio)-4-oxopteridine; phen = 1,10-phenanthroline] also crystallizes in the triclinic space group P1. Unit cell parameters a = 12.414 (2) ?, b = 12.882 (2) ?, c = 11.371 (2) ?, α = 112.55 (2)°, β = 92.58 (1)°, and γ = 83.96 (1)° define a volume of 1670.1 ?3 for Z = 2. The copper coordination sphere has an elongated octahedral geometry defined by four equatorial nitrogen atoms (two from the pteridines and two from phenanthroline) with axial positions filled by oxygen atoms of the pteridine chelates. The third structure reported is for the compound [Cu(phen)2(acetate)] [acetate- H-ethp] (5). In this structure, the pteridine does not chelate copper but is incorporated into the anionic counterion. The compound crystallizes in the monoclinic cell P21/c with parameters a = 11.755 (2) ?, b = 19.079 (2) ?, c = 16.329 (2) ?, and β = 110.36 (1)°, resulting in a cell volume of 3343.6 ?3 for Z = 4. The copper atom is coordinated in a distorted square-pyramidal geometry composed of two phenanthroline chelates and one monodentate acetate ligand. The anion can be formulated as an acetate hydrogen-bonded to the hydroxyl group of the pteridine enol tautomer. A comparison of EPR parameters for the copper complexes reported in this manuscript with previous data for copper pterin complexes reveals that only the value of A∥ is sensitive to variation in copper environments. Spectroscopic and structural data point to a stronger metal-pterin interaction for equatorially bound pterinate ligands. Preliminary results of copper(II) reduction by tetrahydropterin are also presented.
