Novel chromium trinuclear trifluoroacetate complexes Cr3(μ3-O)(CF3COO)6(CH3COOH)2(CF3COO) and Cr3(μ3-O)(CF3COO)6(CH3COOH)2(THF): Synthesis and crystal structure

Abstract

Novel anhydrous trinuclear µ 3 -oxo complexes of Cr(III), ë r 3 (µ 3 -O)(CF 3 COO) 6 (CH 3 COOH) 2 (CF 3 COO) (I) and of Cr(III,III,II), Cr 3 (µ 3 -O)(CF 3 COO) 6 (CH 3 COOH) 2 (THF) (II) (where THF is (CH 2 ) 4 O) are synthesized by anodic dissolution of metallic chromium in solutions of trifluoroacetic acid in acetonitrile and in tetrahydrofuran and their structures are studied by X-ray diffraction analysis. Complex I forms orthorhombic crystals with space group Pna2 1 , a = 9.778 (1) Å, b = 16.042(2) Å, c = 22.851(4) Å, Z = 4, R 1 = 0.0332; complex II crystallizes in monoclinic system: space group P2 1 /c, a = 9.866(1) Å, b = 17.895(2) Å, c = 21.167(4) Å, β = 100.75(2)°, Z = 4, R = 0.0422. The average Cr-(µ 3 -O) distances in compounds I and II are almost equal (1.943(3) and 1.927(3) Å). An average length of the Cr-O bond in octahedral surrounding of metal atoms is different in complexes I and II (1.985(4) and 2.003(3) Å, respectively), which is specified by different oxidation states of the metal atom. The Cr···Cr distances lie in an interval of 3.366(1)-3.337(1) Å.

Metal–Organic Derivatives with Fluorinated Ligands as Precursors for Inorganic Nanomaterials

“…The trivalent or mixed-valent metal complexes of the types [M 3 (μ 3 -O)­(μ-O 2 CR f ) 7 (L) 2 ] and [M 3 (μ 3 -O)­(μ-O 2 CR f ) 6 (L) 3 ] (M = V, Cr; R f = CF 3 , CHF 2 ; L = TFAH, THF, py, Et 2 O, toluene) have classical triangular structure. − The tetranuclear structure of [V 4 (μ 3 -Cl) 2 (μ-Cl) 2 (μ-TFA) 4 (THF) 6 ] has four V­(II) centers bridged by two μ 3 -Cl, two μ-Cl, and four μ-TFA ligands to give an almost planar rhombus. Although all four V­(II) centers are hexacoordinated, they are in two distinct coordination environments: one that is connected to both μ 3 -Cl groups and has only one THF molecule coordinated, and the other that is bonded with only one μ 3 -Cl and has two THF molecules attached with it.…”

Extractants Based on Coordinating Liquid Polar Solvents for Removal of Sulfur Compounds from Diesel Fuels

“…Metal salts used were cadmium chloride hemi(pentahydrate), CdCl Metal trifluoroacetates, i.e., Co(TFA) 2 cobalt trifluoroacetate, Mn(TFA) 2 manganese trifluoroacetate, and Cu(TFA) 2 copper trifluoroacetate were prepared by the methods of obtaining metal acetates described in [11][12][13][14].…”