E. V. Karpova

SYNTHESIS AND CRYSTAL STRUCTURE OF COPPER(II) TRIFLUOROACETATES, CU2(CF3COO)4.2 CH3CN AND CU(CF3COO)2(H2O)4

Cu2(CF3COO)4 · 2 CH3CN (I) and Cu(CF3COO)2(H2O)4 (II) have been prepared by concentrating of acetonitrile and aqueous solutions respectively. According to X-ray data, the complex I consists of binuclear molecules with Cu–O 1.969 A, Cu–N 2.114 A. The Cu…Cu distance was found to be 2.766 A, one of the longest for dimeric structures, apparently, due to the high acidity of trifluoroacetic acid. The coordination environment of Cu atom in II can be described as 4 + 2: 2 Cu–O (H2O) 1.937 A, 2 Cu–O (CF3COO) 1.985 A, 2 Cu–O (H2O) 2.447 A. The mononuclear structure is stabilized by formation of two intra- and six intermolecular hydrogen bonds. Synthese und Kristallstruktur der Kupfer(II)-trifluoroacetat Cu2(CF3COO)4 · 2 CH3CN und Cu(CF3COO)2(H2O)4 Cu2(CF3COO)4 · 2 CH3CN (I) und Cu(CF3COO)2(H2O)4 (II) wurden durch Konzentrieren von Losungen in Acetonitril (I) bzw. Wasser (–10 °C) (II) erhalten. Die Struktur von I besteht aus zweikernigen Komplexen mit Cu–O 1.969 A, Cu–N 2.114 A. Der Cu…Cu-Abstand ist mit 2.766 A fur dimere Strukturen einer der langsten bisher gefundenen, offenbar als Folge der hohen Aciditat der Trifluoressigsaure. Die koordinative Umgebung von Cu in II kann mit 4 + 2 beschrieben werden: 2 Cu–O (H2O) 1.937 A, 2 Cu–O (CF3COO) 1.985 A, 2 Cu–O (H2O) 2.447 A. Die einkernige Struktur wird durch zwei intra- und sechs intermolekulare Wasserstoffbrucken stabilisiert.

Alkali metal and ammonium fluoro(trifluoroacetato)metallates M′[M′′3(μ3-F)(CF3COO)6(CF3COOH)3], where M′ = Li, Na, K, NH4, Rb, or Cs and M′′ = Ni or Co. Synthesis and crystal structures

A series of fluoro(trifluoroacetato)metallates were synthesized by crystallization from solutions in trifluoroacetic acid containing nickel(II) or cobalt(II) nitrate hydrates and alkali metal or ammonium fluorides: Li[Ni3(μ3-F)(CF3COO)6(CF3COOH)3](CF3COOH)3 (I), M′[Ni3(μ3-F)(CF3COO)6(CF3COOH)3] (M′ = Na (II), NH4 (IV), Rb (V), and Cs (VI)), NH4[Co3(μ3-F) (CF3COO)6(CF3COOH)3] (III), and Cs[Ni3(μ3-F)(CF3COO)6(CF3COOH)3](CF3COOH)0.5 (VII). The crystal structures of these compounds were determined by single-crystal X-ray diffraction. All structures contain triangular trinuclear complex anions [M3″(μ3-F)(CF3COO)6(CF3COOH)3]− (M″ = Ni, Co) structurally similar to trinuclear 3d metal oxo carboxylate complexes. The three-coordinated F atom is located at the center of the triangle formed by Ni(II) or Co(II) atoms. The metal atoms are linked in pairs by six bridging trifluoroacetate groups located above and below the plane of the [M″3 F] triangle. The oxygen atoms of the axial CF3COOH molecules complete the coordination environment of M″ atoms to an octahedron.

Synthesis and structure of acetonitrile solvates of copper(II) monofluoroacetate and silver(I) trifluoroacetate, [Cu2(CH2FCOO)4·2CH 3CN](CH3CN) and Ag3(CF3COO)3(CH3CN)2

AbstractCompounds [Cu2(CH2FCOO)4· 2CH3CN](CH3CN) (I) and Ag3(CF3COO)3(CH3CN)2(II) were synthesized and studied by X-ray structural analysis. Crystals Iare monoclinic, space group C2/c, a= 27.854(6), b= 8.286(2), c= 19.428(4) Å, β = 106.82(3)°, V= 4292(2) Å3, Z= 8, R1= 0.0426; crystals IIare triclinic, space group

Thulium(III) trifluoroacetates Tm(CF3COO)3 · 3H2O and Tm2(CF3COO)6 · 2CF3COOH · 3H2O: Synthesis and crystal structure

P\overline 1

Nonenzymatic Sensor for Lactate Detection in Human Sweat

, a= 8.676(2), b= 9.819(2), c= 11.961(2) Å, α = 95.27(3), β = 109.59(3)°, γ = 104.60(3)°, V= 911.4(3) Å3, Z= 2, R1= 0.0252. Structure Iis composed of the structural units (“lanterns”) typical of copper(II) carboxylates. The presence of an additional acetonitrile molecule noncoordinated by the copper atoms makes it possible to consider compound Ias a lattice clathrate. Structure IIhas no analogs among the silver carboxylates. It simultaneously contains silver atoms with coordination numbers varying from 2 to 4.

Ab initio calculations of the structure, vibrational spectra, and thermodynamic properties of silver trifluoroacetates

An advanced electrocatalyst for H2O2 reduction was synthesized via the deposition of an iron- and nickel hexacyanoferrate bilayer and displayed a similar electrocatalytic activity (≈0.01 cm s−1) and an almost 100-fold improved operational stability compared to Prussian Blue. The electrocatalyst was highly reproducible, with a deviation in both the operational stability and catalytic activity among different modified electrodes of <10%.

Oxonitrates VO(NO3)3 and MoO2(NO3)2 and nitronium and nitrosonium nitratometallates as nitrating agents

Thulium trifluoroacetate compounds have been synthesized, Tm(CF3COO)3 · 3H2O (I) and Tm2(CF3COO)6 · 2CF3COOH · 3H2O (II). The structure of I has been refined by the Rietveld method on the basis of the structural data for Cd(CF3COO)3 · 3H2O. The structure of II has been solved in a single-crystal X-ray diffraction study. Compound I has been studied by thermal analysis. Crystals of I and II are monoclinic: for Ia = 9.062(2) Å, b = 18.678(3) Å, c = 9.687(2) Å, β = 113.93(1)°, Z = 2, space group P21/c, R1 = 0.062; for IIa = 8.560(4) Å, b = 19.866(5) Å, c = 20.813(7) Å, β = 101.69(4)°, Z = 8, space group C2/c, R1 = 0.0392. In the molecular structure of I, thulium atoms are bonded in pairs through four bridging trifluoroacetate anions to form dimers. The coordination polyhedron of the thulium atom also includes the three O atoms of the water molecules and the O atom of the monodentate trifluoroacetate group; the coordination number of the thulium atom is eight. In the chain structure of II, there are two crystallographically independent thulium atoms with coordination numbers 8 and 9. The coordination polyhedra of the Tm(1) and Tm(2) atoms are a distorted monocapped tetragonal antiprism and a distorted tetragonal antiprism, respectively. The Tm-O bond lengths are in the range 2.28(1)–2.85(2) Å. The thulium atoms are bound into chains through carboxylate groups. These chains are linked into layers through hydrogen bonds.

Tris(ethane-1,2-diamine)copper(II) bis-(trifluoro-acetate).

The asymmetric unit of the title compound, 2C2H8N+·C8H4O42−, comprises two crystallographically independent dimethylammonium cations and two half-terephthalate anions. The latter are each disposed about an inversion centre. N—H⋯O hydrogen bonds link the ions into a three-dimensional framework.