Copper(II) Acetate as a Motif for Metal-Assembled Complexes

Abstract

AccountsIn this review, a new method for the preparation of metal-assembled complexes based on copper(II) acetate type dinuclear systems has been reported. A variety of coordination modes of carboxylato group were classified into ten types of groups including bis-, tris-, and tetrakis-bridging based on our complexes and discussed in relation to mononuclear, dinuclear, oligonuclear, and polynuclear systems. An interdimer interaction could not be observed in temperature dependence of magnetic susceptibilities at 4.5-300 K region in case of one-dimensional chain systems of copper(II) pivalate with N,N'-bidentate ligands such as pyrazine, 4,4'-bipyridine, 1,4-diazabicyclo[2.2 .2]octane. Adsorption property for nitrogen gas was found in a chain system of copper(II) benzoate with pyrazine. Mesomorphic properties were also found for chain systems of copper(II) carboxylates with long alkyl chains. By using copper(II) trichloroacetate, a chain molecule consisting of alternated arrangement of tetranuclear cubane and pyrazine was isolated. Two-dimensional and three-dimensional assembled complexes were obtained by reactions of copper(II) trifluoroacetate and copper(II) propionate, respectively, with pyrazine. Bis-adducts of copper(II) propionate with pyridyl nitronyl nitroxides, copper(II) acetate with a stable adamantanyloxyamino radical, and dinuclear copper(II) complexes with 4-carboxy-2,2,6,6-tetramethylpiperidinyloxy and 3-carboxy-2,2,5,5tetramethyl-1-pyrrolidinyloxy were prepared as radical-containing copper(II) acetate systems. ( 1) Chemical Abstract Copper Acetate 8380 , Jonassen, Fanning Doedens 2) 3,7) Thornton 4) Corresponding Author: Masahiro Mikuriya Address: Gakuen 2-1, Sanda 669-1337, Japan

Chain Compounds Based on Paddle-wheel Copper(II) Carboxylate Bearing Four Nitroxide Radicals

“…The Cu···Cu' distance is 2.6018(4) Å. This feature is normal as the copper acetate type clusters [3][4][5][6][7]. The N1-O3 and N2-O6 bond distances of the catempo -moieties are 1.2825(17) and 1.2879(15) Å, respectively, which is comparable to that of tempo radical (1.283(9) Å) [36], showing a normal distance as a free nitroxide radical.…”

“…The diffused reflectance spectra of all the compounds (Figure 4) can be characterized as three main absorption bands, as previously reported for copper(II) acetate type cluster systems [5,7]. The ligand to metal charge transfer is responsible for the high intensity bands in the UV region.…”

“…The ligand to metal charge transfer is responsible for the high intensity bands in the UV region. The shoulder-like absorption band at near-UV region can be assumed as a characteristic band of copper(II) acetate type clusters [5,7]. Furthermore, all broad bands spanned in the visible and NIR regions until around 1000 nm are typically interpreted as d-d transitions [35].…”

“…Copper acetate is one of the old-fashioned metal complexes with a paddle-wheel-like or lantern-like cluster and has attracted much attention since the discovery of the unique dinuclear structure with antiferromagnetic spin-coupling [1][2][3][4][5][6][7]. We have engaged in the synthesis of copper acetate analogues and their coordination polymer complexes [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24].…”

Synthesis, thermal study and some properties of Zn(II), Cd(II) and Pb(II) compounds with mono-, di- and trichloroacetates

“…Substituents of the carboxylic acids have an impact on acidity. A carboxylate group as a ligand can coordinate with metal ion in various ways [1], making it interesting. The title chloroacetic acid is widely used.…”