Names | |
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IUPAC name Copper(I) iodide | |
Other names Cuprous iodide, marshite | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.028.795 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
CuI | |
Molar mass | 190.45 g/mol |
Appearance | White solid |
Odor | odorless |
Density | 5.67 g/cm3 [1] |
Melting point | 606 °C (1,123 °F; 879 K) |
Boiling point | 1,290 °C (2,350 °F; 1,560 K) (decomposes) |
0.000042 g/100 mL | |
Solubility product (Ksp) | 1.27 x 10−12 [2] |
Solubility | soluble in ammonia and iodide solutions insoluble in dilute acids |
Vapor pressure | 10 mm Hg (656 °C) |
-63.0·10−6 cm3/mol | |
Refractive index (nD) | 2.346 |
Structure | |
zincblende | |
Tetrahedral anions and cations | |
Hazards | |
GHS labelling: | |
Danger | |
H302, H315, H319, H335, H410 | |
P261, P273, P305+P351+P338, P501 | |
NFPA 704 (fire diamond) | |
Flash point | Non-flammable |
NIOSH (US health exposure limits): | |
PEL (Permissible) | TWA 1 mg/m3 (as Cu) [3] |
REL (Recommended) | TWA 1 mg/m3 (as Cu) [3] |
IDLH (Immediate danger) | TWA 100 mg/m3 (as Cu) [3] |
Safety data sheet (SDS) | Sigma Aldrich [4] |
Related compounds | |
Other anions | |
Other cations | silver iodide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Copper(I) iodide is the inorganic compound with the formula CuI. It is also known as cuprous iodide. It is useful in a variety of applications ranging from organic synthesis to cloud seeding.
Copper(I) iodide is white, but samples often appear tan or even, when found in nature as rare mineral marshite, reddish brown, but such color is due to the presence of impurities. It is common for samples of iodide-containing compounds to become discolored due to the facile aerobic oxidation of the iodide anion to molecular iodine. [5] [6] [7]
Copper(I) iodide, like most binary (containing only two elements) metal halides, is an inorganic polymer. It has a rich phase diagram, meaning that it exists in several crystalline forms. It adopts a zinc blende structure below 390 °C (γ-CuI), a wurtzite structure between 390 and 440 °C (β-CuI), and a rock salt structure above 440 °C (α-CuI). The ions are tetrahedrally coordinated when in the zinc blende or the wurtzite structure, with a Cu-I distance of 2.338 Å. Copper(I) bromide and copper(I) chloride also transform from the zinc blende structure to the wurtzite structure at 405 and 435 °C, respectively. Therefore, the longer the copper – halide bond length, the lower the temperature needs to be to change the structure from the zinc blende structure to the wurtzite structure. The interatomic distances in copper(I) bromide and copper(I) chloride are 2.173 and 2.051 Å, respectively. [8] Consistent with its covalency, CuI is a p-type semiconductor. [9]
γ-CuI | β-CuI | α-CuI |
Copper(I) iodide can be prepared by heating iodine and copper in concentrated hydriodic acid. [10]
In the laboratory however, copper(I) iodide is prepared by simply mixing an aqueous solution of potassium iodide and a soluble copper(II) salt such copper sulfate. [11]
Cuprous iodide, which degrades on standing, can be purified by dissolution into concentrated solution of potassium iodide followed by dilution. [5]
Copper(I) iodide reacts with mercury vapors to form copper tetraiodomercurate:
This reaction can be used for the detection of mercury since the white (CuI) to brown (Cu2HgI4) color change is dramatic.
Copper(I) iodide is used in the synthesis of Cu(I) clusters. [12] which is polymetal complex compounds.
Copper(I) iodide dissolves in acetonitrile, yielding a diverse complexes. Upon crystallization, molecular [13] or polymeric [14] [15] compounds can be isolated. Dissolution is also observed when a solution of the appropriate complexing agent in acetone or chloroform is used. For example, thiourea and its derivatives can be used. Solids that crystallize out of those solutions are composed of hybrid inorganic chains. [16]
CuI is used as a reagent in organic synthesis. In combination with 1,2- or 1,3 diamine ligands, CuI catalyzes the conversion of aryl-, heteroaryl-, and vinyl-bromides into the corresponding iodides. NaI is the typical iodide source and dioxane is a typical solvent (see aromatic Finkelstein reaction). [17] Aryl halides are used to form carbon–carbon and carbon–heteroatom bonds in process such as the Heck, Stille, Suzuki, Sonogashira and Ullmann type coupling reactions. Aryl iodides, however, are more reactive than the corresponding aryl bromides or aryl chlorides. 2-Bromo-1-octen-3-ol and 1-nonyne are coupled when combined with dichlorobis(triphenylphosphine)palladium(II), CuI, and diethylamine to form 7-methylene-8-hexadecyn-6-ol. [18]
CuI is used in cloud seeding, [19] altering the amount or type of precipitation of a cloud, or their structure by dispersing substances into the atmosphere which increase water's ability to form droplets or crystals. CuI provides a sphere for moisture in the cloud to condense around, causing precipitation to increase and cloud density to decrease.
The structural properties of CuI allow CuI to stabilize heat in nylon in commercial and residential carpet industries, automotive engine accessories, and other markets where durability and weight are a factor.[ citation needed ]
CuI is used as a source of dietary iodine in table salt and animal feed. [19]
Silver iodide is an inorganic compound with the formula AgI. The compound is a bright yellow solid, but samples almost always contain impurities of metallic silver that give a gray coloration. The silver contamination arises because some samples of AgI can be highly photosensitive. This property is exploited in silver-based photography. Silver iodide is also used as an antiseptic and in cloud seeding.
In organic chemistry, an aryl halide is an aromatic compound in which one or more hydrogen atoms, directly bonded to an aromatic ring are replaced by a halide. The haloarene are different from haloalkanes because they exhibit many differences in methods of preparation and properties. The most important members are the aryl chlorides, but the class of compounds is so broad that there are many derivatives and applications.
The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon–carbon bonds. It employs a palladium catalyst as well as copper co-catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or vinyl halide.
Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl. The substance is a white solid sparingly soluble in water, but very soluble in concentrated hydrochloric acid. Impure samples appear green due to the presence of copper(II) chloride (CuCl2).
The Corey–House synthesis is an organic reaction that involves the reaction of a lithium diorganylcuprate with an organic halide or pseudohalide to form a new alkane, as well as an ill-defined organocopper species and lithium (pseudo)halide as byproducts.
The Ullmann condensation or Ullmann-type reaction is the copper-promoted conversion of aryl halides to aryl ethers, aryl thioethers, aryl nitriles, and aryl amines. These reactions are examples of cross-coupling reactions.
Copper(I) cyanide is an inorganic compound with the formula CuCN. This off-white solid occurs in two polymorphs; impure samples can be green due to the presence of Cu(II) impurities. The compound is useful as a catalyst, in electroplating copper, and as a reagent in the preparation of nitriles.
The Finkelstein reaction named after the German chemist Hans Finkelstein, is an SN2 reaction that involves the exchange of one halogen atom for another. It is an equilibrium reaction, but the reaction can be driven to completion by exploiting the differential solubility of halide salts, or by using a large excess of the halide salt.
Aluminium iodide is a chemical compound containing aluminium and iodine. Invariably, the name refers to a compound of the composition AlI
3, formed by the reaction of aluminium and iodine or the action of HI on Al metal. The hexahydrate is obtained from a reaction between metallic aluminum or aluminum hydroxide with hydrogen iodide or hydroiodic acid. Like the related chloride and bromide, AlI
3 is a strong Lewis acid and will absorb water from the atmosphere. It is employed as a reagent for the scission of certain kinds of C-O and N-O bonds. It cleaves aryl ethers and deoxygenates epoxides.
Organozinc chemistry is the study of the physical properties, synthesis, and reactions of organozinc compounds, which are organometallic compounds that contain carbon (C) to zinc (Zn) chemical bonds.
Organocopper chemistry is the study of the physical properties, reactions, and synthesis of organocopper compounds, which are organometallic compounds containing a carbon to copper chemical bond. They are reagents in organic chemistry.
Copper(I) bromide is the chemical compound with the formula CuBr. This diamagnetic solid adopts a polymeric structure akin to that for zinc sulfide. The compound is widely used in the synthesis of organic compounds and as a lasing medium in copper bromide lasers.
Group 2 organometallic chemistry refers to the chemistry of compounds containing carbon bonded to any group 2 element. By far the most common group 2 organometallic compounds are the magnesium-containing Grignard reagents which are widely used in organic chemistry. Other organmetallic group 2 compounds are rare and are typically limited to academic interests.
Bromopentacarbonylrhenium(I) is an inorganic compound of rhenium, commonly used for the syntheses of other rhenium complexes.
Organorhenium chemistry describes the compounds with Re−C bonds. Because rhenium is a rare element, relatively few applications exist, but the area has been a rich source of concepts and a few useful catalysts.
In organometallic chemistry, metal–halogen exchange is a fundamental reaction that converts an organic halide into an organometallic product. The reaction commonly involves the use of electropositive metals and organochlorides, bromides, and iodides. Particularly well-developed is the use of metal–halogen exchange for the preparation of organolithium compounds.
Phosphide iodides or iodide phosphides are compounds containing anions composed of iodide (I−) and phosphide (P3−). They can be considered as mixed anion compounds. They are in the category of pnictidehalides. Related compounds include the phosphide chlorides, arsenide iodides antimonide iodides and phosphide bromides.
Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. Copper compounds, whether organic complexes or organometallics, promote or catalyse numerous chemical and biological processes.
Rhenium compounds are compounds formed by the transition metal rhenium (Re). Rhenium can form in many oxidation states, and compounds are known for every oxidation state from -3 to +7 except -2, although the oxidation states +7, +6, +4, and +2 are the most common. Rhenium is most available commercially as salts of perrhenate, including sodium and ammonium perrhenates. These are white, water-soluble compounds. Tetrathioperrhenate anion [ReS4]− is possible.
Hafnium(III) iodide is an inorganic compound of hafnium and iodine with the formula HfI3. It is a black solid.