Benedict's reagent is a chemical reagent and complex mixture of sodium carbonate, sodium citrate, and copper(II) sulfate pentahydrate. It is often used in place of Fehling's solution to detect the presence of reducing sugars. The presence of other reducing substances also gives a positive result. Such tests that use this reagent are called the Benedict's tests. A positive test with Benedict's reagent is shown by a color change from clear blue to brick-red with a precipitate.
In organic chemistry, Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reagent test. The test was developed by German chemist Hermann von Fehling in 1849.
Copper(I) oxide or cuprous oxide is the inorganic compound with the formula Cu2O. It is one of the principal oxides of copper, the other being copper(II) oxide or cupric oxide (CuO).The compound can appear either yellow or red, depending on the size of the particles. Cuprous oxide is found as the mineral cuprite. It is a component of some antifouling paints, but also has other applications including some that exploit its property as a semiconductor.
Cuprates are a class of compounds that contain copper (Cu) atom(s) in an anion. They can be broadly categorized into two main types:
Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu2O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite. It is a product of copper mining and the precursor to many other copper-containing products and chemical compounds.
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).
Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group [R−N+≡N]X− where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide. The parent compound where R is hydrogen, is diazenylium.
Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is a strong base, although its low solubility in water makes this hard to observe directly.
Copper monosulfide is a chemical compound of copper and sulfur. It was initially thought to occur in nature as the dark indigo blue mineral covellite. However, it was later shown to be rather a cuprous compound, formula Cu+3S(S2). CuS is a moderate conductor of electricity. A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts. It is one of a number of binary compounds of copper and sulfur (see copper sulfide for an overview of this subject), and has attracted interest because of its potential uses in catalysis and photovoltaics.
Tetrakis(acetonitrile)copper(I) hexafluorophosphate is a salt with the formula [Cu(CH3CN)4]PF6. It is a colourless solid that is used in the synthesis of other copper complexes. The cation [Cu(CH3CN)4]+ is a well-known example of a transition metal nitrile complex.
Dicopper chloride trihydroxide is the chemical compound with the chemical formula Cu2(OH)3Cl. It is often referred to as tribasic copper chloride (TBCC), copper trihydroxyl chloride or copper hydroxychloride. It is a greenish crystalline solid encountered in mineral deposits, metal corrosion products, industrial products, art and archeological objects, and some living systems. It was originally manufactured on an industrial scale as a precipitated material used as either a chemical intermediate or a fungicide. Since 1994, a purified, crystallized product has been produced at the scale of thousands of tons per year, and used extensively as a nutritional supplement for animals.
Metal carbon dioxide complexes are coordination complexes that contain carbon dioxide ligands. Aside from the fundamental interest in the coordination chemistry of simple molecules, studies in this field are motivated by the possibility that transition metals might catalyze useful transformations of CO2. This research is relevant both to organic synthesis and to the production of "solar fuels" that would avoid the use of petroleum-based fuels.
Delafossite is a copper iron oxide mineral with formula CuFeO2 or Cu1+Fe3+O2. It is a member of the delafossite mineral group, which has the general formula ABO2, a group characterized by sheets of linearly coordinated A cations stacked between edge-shared octahedral layers (BO6). Delafossite, along with other minerals of the ABO2 group, is known for its wide range of electrical properties, its conductivity varying from insulating to metallic. Delafossite is usually a secondary mineral that crystallizes in association with oxidized copper and rarely occurs as a primary mineral.
Copper(I) sulfate, also known as cuprous sulfate, is an inorganic compound with the chemical formula Cu2SO4. It is a white solid, in contrast to copper(II) sulfate, which is blue in hydrous form. Compared to the commonly available reagent, copper(II) sulfate, copper(I) sulfate is unstable and not readily available.
Copper hydride is an inorganic compound with the chemical formula CuHn where n ~ 0.95. It is a red solid, rarely isolated as a pure composition, that decomposes to the elements. Copper hydride is mainly produced as a reducing agent in organic synthesis and as a precursor to various catalysts.
In organometallic chemistry, palladium-NHC complexes are a family of organopalladium compounds in which palladium forms a coordination complex with N-heterocyclic carbenes (NHCs). They have been investigated for applications in homogeneous catalysis, particularly cross-coupling reactions.
In coordination chemistry, a transition metal NHC complex is a metal complex containing one or more N-heterocyclic carbene ligands. Such compounds are the subject of much research, in part because of prospective applications in homogeneous catalysis. One such success is the second generation Grubbs catalyst.
Coinage metal N-heterocyclic carbene (NHC) complexes refer to transition metal complexes incorporating at least one coinage metal center (M = Cu, Ag, Au) ligated by at least one NHC-type persistent carbene. A variety of such complexes have been synthesized through deprotonation of the appropriate imidazolium precursor and metalation by the appropriate metal source, producing MI, MII, or MIII NHC complexes. While the general form can be represented as (R2N)2C:–M (R = various alkyl or aryl groups), the exact nature of the bond between NHC and M has been investigated extensively through computational modeling and experimental probes. These results indicate that the M-NHC bond consists mostly of electrostatic attractive interactions, with some covalent bond character arising from NHC to M σ donation and minor M to NHC π back-donation. Coinage metal NHC complexes show effective activity as catalysts for various organic transformations functionalizing C-H and C-C bonds, and as antimicrobial and anticancer agents in medicinal chemistry.
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.
