Tetrakis(acetonitrile)copper(I) hexafluorophosphate
Structural formulas of the tetrakis(acetonitrile)copper(I) cation and the hexafluorophosphate anion | |
Space-filling models of the component ions of tetrakis(acetonitrile)copper(I) hexafluorophosphate | |
Names | |
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IUPAC name
Tetrakis(acetonitrile)copper(I) hexafluorophosphate
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Identifiers | |
64443-05-6 | |
Properties | |
[Cu(CH3CN)4]PF6 | |
Molar mass | 372.7198 g/mol |
Appearance | White powder |
Melting point | 160 °C (320 °F; 433 K) |
Vapor pressure | {{{value}}} |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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verify (what is ?) | |
Infobox references | |
Tetrakis(acetonitrile)copper(I) hexafluorophosphate is a coordination compound with the formula [Cu(CH3CN)4]PF6. It is a colourless solid that is used in the synthesis of copper complexes.[1]
Structure
As confirmed by X-ray crystallographic studies, copper(I) ion is coordinated to four almost linear acetonitrile ligands in a nearly ideal tetrahedral geometry.[2] Related complexes are known with other anions including the perchlorate, tetrafluoroborate, and nitrate. With the weakly coordinating anion B(C6F5)4−, salts of [Cu(CH3CN)2]+ are obtained.[1]
The acetonitrile ligands protect the Cu+ ion from oxidation to Cu2+. However, acetonitrile is not bound very strongly to the copper ion, thus the complex is a useful source of Cu(I).
Synthesis
The cation was first reported in 1923 with a nitrate anion as a byproduct of the reduction of silver nitrate with a suspension of copper powder in acetonitrile.[3] [Cu(CH3CN)4]PF6 is generally produced by the addition of HPF6 to a suspension of copper(I) oxide in acetonitrile:[4]
- Cu2O + 2 HPF6 + 8 CH3CN → 2 [Cu(CH3CN)4]PF6 + H2O
The reaction is highly exothermic, and may bring the solution to a boil. Upon crystallization, the resulting microcrystals should be white, though a blue tinge is common, indicating the presence of a Cu2+ species.[4]
Reactions and applications
As the coordinated acetonitrile ligands may be displaced in other solvents, the [Cu(CH3CN)4]PF6 compound may serve as a precursor in the non-aqueous syntheses of other Cu(I) compounds.[4]
Water-immiscible organic nitriles have been shown to selectively extract Cu2+ from aqueous chloride solutions.[5] Through this method, copper can be separated from a mixture of other metals. Dilution of acetonitrile solutions with water induces disproportionation:
- 2 [Cu(CH3CN)4]+ + 6 H2O → [Cu(H2O)6]2+ + Cu + 8 CH3CN
References
- ↑ 1.0 1.1 Silvana F. Rach, Fritz E. Kühn "Nitrile Ligated Transition Metal Complexes with Weakly Coordinating Counteranions and Their Catalytic Applications" Chem. Rev., 2009, volume 109, pp 2061–2080. doi:10.1021/cr800270h
- ↑ Lua error in package.lua at line 80: module 'strict' not found.J. R. Black, W. Levason and M. Webster "Tetrakis(acetonitrile-N)copper(I) Hexafluorophosphate(V) Acetonitrile Solvate"Acta Crystallogr. (1995). C51, pp. 623-625. doi:10.1107/S0108270194012527
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 4.0 4.1 4.2 Lua error in package.lua at line 80: module 'strict' not found.
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