Copper(II) acetate
Copper(II) acetate, also referred to as cupric acetate, is the chemical compound with the formula Template:Chem2 where Template:Chem2 is acetate (Template:Chem2). The hydrated derivative, Template:Chem2, which contains one molecule of water for each copper atom, is available commercially. Anhydrous copper(II) acetate is a dark green crystalline solid, whereas Template:Chem2 is more bluish-green. Since ancient times, copper acetates of some form have been used as fungicides and green pigments. Today, copper acetates are used as reagents for the synthesis of various inorganic and organic compounds.[1] Copper acetate, like all copper compounds, emits a blue-green glow in a flame.
Structure
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Synthesis
Copper(II) acetate is prepared industrially by heating copper(II) hydroxide or basic copper(II) carbonate with acetic acid.[1]
Uses in chemical synthesis
Copper(II) acetate has found some use as an oxidizing agent in organic syntheses. In the Eglinton reaction Template:Chem2 is used to couple terminal alkynes to give a 1,3-diyne:[9][10]
The reaction proceeds via the intermediacy of copper(I) acetylides, which are then oxidized by the copper(II) acetate, releasing the acetylide radical. A related reaction involving copper acetylides is the synthesis of ynamines, terminal alkynes with amine groups using Cu2(OAc)4.[11] It has been used for hydroamination of acrylonitrile.[12]
In chemical analysis, it serves as an oxidizing agent in both the Barfoed's test for presence of monosaccharides and as a precursor to a copper-fatty acid complex in the colorimetric copper soap assay to test for free fatty acids.[13]
It reacts with arsenic trioxide to form copper acetoarsenite, a powerful insecticide and fungicide called Paris green.
Related compounds
Heating a mixture of anhydrous copper(II) acetate and copper metal affords copper(I) acetate:[14][15]
Unlike the copper(II) derivative, copper(I) acetate is colourless and diamagnetic.
"Basic copper acetate" is prepared by neutralizing an aqueous solution of copper(II) acetate. The basic acetate is poorly soluble. This material is a component of verdigris, the blue-green substance that forms on copper during long exposures to atmosphere.Script error: No such module "Unsubst".
Other uses
A mixture of copper acetate and ammonium chloride is used to chemically color copper with a bronze patina.[16]
Mineralogy
The mineral hoganite is a naturally occurring form of copper(II) acetate.[17][18] A related mineral, also containing calcium, is paceite.[18] Both are very rare.[19][20]
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References
External links
- Copper.org – Other Copper Compounds Template:Webarchive 5 Feb. 2006
- Infoplease.com – Paris green 6 Feb. 2006
- Verdigris – History and Synthesis 6 Feb. 2006
- Australian - National Pollutant Inventory 8 Aug. 2016
- USA NIH National Center for Biotechnology Information 8 Aug. 2016
Template:Copper compounds Template:Acetates
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