Structure of the cis monohydrate form of bis(glycinato)copper(II) | |
Names | |
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IUPAC name bis(glycinato)copper(II) | |
Other names cupric glycinate | |
Identifiers | |
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3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.033.425 |
EC Number |
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PubChem CID | |
UNII |
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CompTox Dashboard (EPA) | |
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Properties | |
C4H10CuN2O5 | |
Molar mass | 229.679 g·mol−1 |
Appearance | light blue, flake-like crystals (cis form) |
Density | 2.029 g/cm3 |
Melting point | 212 °C (414 °F; 485 K) (decomp.) |
0.18 g/100 g (0 °C) 0.52 g/100 g (25 °C) | |
Solubility | soluble in DMF, DMSO, pyridine; slightly soluble in ethanol |
Structure [1] | |
Orthorhombic | |
№ 19 (P212121) | |
222 | |
a = 5.21 Å, b = 10.81 Å, c = 13.49 Å | |
Formula units (Z) | 4 |
Hazards | |
GHS labelling: | |
Warning | |
H302, H315, H319, H400 | |
P264, P270, P273, P280, P301+P312, P302+P352, P305+P351+P338, P321, P330, P332+P313, P337+P313, P362, P391, P501 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Copper(II) glycinate (IUPAC suggested name: bis(glycinato)copper(II)) refers to the coordination complex of copper(II) with two equivalents of glycinate, with the formula [Cu(glycinate)2(H2O)x] where x = 1 (monohydrate) or 0 (anhydrous form). The complex was first reported in 1841, and its chemistry has been revisited many times, particularly in relation to the isomerisation reaction between the cis and trans forms which was first reported in 1890. [2] [3]
All forms are blue solids, with varying degrees of water solubility. A practical application of the compound is as a source of dietary copper in animal feeds. [4]
Bis(glycinato)copper(II) is typically prepared from the reaction of copper(II) acetate in aqueous ethanol with glycine: [2] [3]
The reaction proceeds through a non-redox dissociative substitution mechanism and usually affords the cis isomer. [2] [3]
Like most amino acid complexes, the glycinate forms a 5-membered chelate ring, with the glycinato ligand serving as a bidentate (κ2Ο,Ν) species. [2] [5] The chelating ligands assume a square planar configuration around the copper atom as is common for tetracoordinate d9 complexes, calculated to be much lower in energy than the alternative tetrahedral arrangement. [3]
The unsymmetric nature of the ligand and square planar coordination thereof gives rise to two possible geometric isomers: a cis and a trans form.
Multiple ways of differentiating the geometric isomers exist, an easily accessible one being IR spectroscopy with the characteristic number of C–N, C–O, and CuII–N identifying the ligand configuration. Crystal appearance may also be of some value for isomer indication, though the ultimate diagnostic technique is X-ray crystallography. [1]
All forms of the complex have been characterized crystallographically, the most commonly isolated one being the cis monohydrate (x = 1). [5] [1]
Isomerisation of the cis to the trans form occurs at high temperatures via a ring-twisting mechanism. [2] [3]
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the coordination centre, and a surrounding array of bound molecules or ions, that are in turn known as ligands or complexing agents. Many metal-containing compounds, especially those that include transition metals, are coordination complexes.
In organic chemistry, a peptide bond is an amide type of covalent chemical bond linking two consecutive alpha-amino acids from C1 of one alpha-amino acid and N2 of another, along a peptide or protein chain.
Chelation is a type of bonding of ions and their molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate ligand and a single central metal atom. These ligands are called chelants, chelators, chelating agents, or sequestering agents. They are usually organic compounds, but this is not a necessity.
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1,10-Phenanthroline (phen) is a heterocyclic organic compound. It is a white solid that is soluble in organic solvents. The 1,10 refer to the location of the nitrogen atoms that replace CH's in the hydrocarbon called phenanthrene.
In coordination chemistry, metal ammine complexes are metal complexes containing at least one ammonia ligand. "Ammine" is spelled this way for historical reasons; in contrast, alkyl or aryl bearing ligands are spelt with a single "m". Almost all metal ions bind ammonia as a ligand, but the most prevalent examples of ammine complexes are for Cr(III), Co(III), Ni(II), Cu(II) as well as several platinum group metals.
Cycloocta-1,5-diene is a cyclic hydrocarbon with the chemical formula C8H12, specifically [−(CH2)2−CH=CH−]2.
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Metal acetylacetonates are coordination complexes derived from the acetylacetonate anion (CH
3COCHCOCH−
3) and metal ions, usually transition metals. The bidentate ligand acetylacetonate is often abbreviated acac. Typically both oxygen atoms bind to the metal to form a six-membered chelate ring. The simplest complexes have the formula M(acac)3 and M(acac)2. Mixed-ligand complexes, e.g. VO(acac)2, are also numerous. Variations of acetylacetonate have also been developed with myriad substituents in place of methyl (RCOCHCOR′−). Many such complexes are soluble in organic solvents, in contrast to the related metal halides. Because of these properties, acac complexes are sometimes used as catalyst precursors and reagents. Applications include their use as NMR "shift reagents" and as catalysts for organic synthesis, and precursors to industrial hydroformylation catalysts. C
5H
7O−
2 in some cases also binds to metals through the central carbon atom; this bonding mode is more common for the third-row transition metals such as platinum(II) and iridium(III).
A metal-phosphine complex is a coordination complex containing one or more phosphine ligands. Almost always, the phosphine is an organophosphine of the type R3P (R = alkyl, aryl). Metal phosphine complexes are useful in homogeneous catalysis. Prominent examples of metal phosphine complexes include Wilkinson's catalyst (Rh(PPh3)3Cl), Grubbs' catalyst, and tetrakis(triphenylphosphine)palladium(0).
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trans-Dichlorodiammineplatinum(II) is the trans isomer of the coordination complex with the formula trans-PtCl2(NH3)2, sometimes called transplatin. It is a yellow solid with low solubility in water but good solubility in DMF. The existence of two isomers of PtCl2(NH3)2 led Alfred Werner to propose square planar molecular geometry. It belongs to the molecular symmetry point group D2h.
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Transition metal thioether complexes comprise coordination complexes of thioether (R2S) ligands. The inventory is extensive.
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cis-1,2-Bis(diphenylphosphino)ethylene (dppv) is an organophosphorus compound with the formula C2H2(PPh2)2 (Ph = C6H5). Both the cis and trans isomers are known, but the cis isomer is of primary interest. Classified as a diphosphine ligand, it is a bidentate ligand in coordination chemistry. For example it gives rise to the complex Ni(dppv)2 and the coordination polymer [Ni(dppv)]n. As a chelating ligand, dppv is very similar to 1,2-bis(diphenylphosphino)benzene.
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