The Zerewitinoff determination or Zerevitinov determination is a quantitative chemical test for the determination of active hydrogens in a chemical substance [1] developed by F. V. Tserevitinov (jointly with L. A. Chugaev ) in 1902-1907. A sample is treated with the Grignard reagent, methylmagnesium iodide, which reacts with any acidic hydrogen atom to form methane. This gas can be determined quantitatively by measuring its volume. For example:
The Pinner reaction refers to the acid catalysed reaction of a nitrile with an alcohol to form an imino ester salt ; this is sometimes referred to as a Pinner salt. The reaction is named after Adolf Pinner, who first described it in 1877. Pinner salts are themselves reactive and undergo additional nucleophilic additions to give various useful products:
In organic chemistry, an imine is a functional group or organic compound containing a carbon–nitrogen double bond. The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bonds. Imines are common in synthetic and naturally occurring compounds and they participate in many reactions.
In organic chemistry, a nitrile is any organic compound that has a −C≡N functional group. The name of the compound is composed of a base, which includes the carbon of the −C≡N, suffixed with "nitrile", so for example CH3CH2C≡N is called "propionitrile". The prefix cyano- is used interchangeably with the term nitrile in industrial literature. Nitriles are found in many useful compounds, including methyl cyanoacrylate, used in super glue, and nitrile rubber, a nitrile-containing polymer used in latex-free laboratory and medical gloves. Nitrile rubber is also widely used as automotive and other seals since it is resistant to fuels and oils. Organic compounds containing multiple nitrile groups are known as cyanocarbons.
Phenanthrene is a polycyclic aromatic hydrocarbon (PAH) with formula C14H10, consisting of three fused benzene rings. It is a colorless, crystal-like solid, but can also appear yellow. Phenanthrene is used to make dyes, plastics, pesticides, explosives, and drugs. It has also been used to make bile acids, cholesterol and steroids.
Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative quantities of the other constituents are known.
In chemistry, a chemical test is a qualitative or quantitative procedure designed to identify, quantify, or characterise a chemical compound or chemical group.
The Griess test is an analytical chemistry test which detects the presence of nitrite ion in solution. One of its most important uses is the determination of nitrite in drinking water. The Griess diazotization reaction, on which the Griess reagent relies, was first described in 1858 by Peter Griess. The test has also been widely used for the detection of nitrates, which are a common component of explosives, as they can be reduced to nitrites and detected with the Griess test.
The Bouveault–Blanc reduction is a chemical reaction in which an ester is reduced to primary alcohols using absolute ethanol and sodium metal. It was first reported by Louis Bouveault and Gustave Louis Blanc in 1903. Bouveault and Blanc demonstrated the reduction of ethyl oleate and n-butyl oleate to oleyl alcohol. Modified versions of which were subsequently refined and published in Organic Syntheses.
In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group. If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily breaks, producing free radicals of the form RO•. Thus, organic peroxides are useful as initiators for some types of polymerization, such as the acrylic, unsaturated polyester, and vinyl ester resins used in glass-reinforced plastics. MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can explosively combust. Organic peroxides, like their inorganic counterparts, are often powerful bleaching agents.
The Zeisel determination or Zeisel test is a chemical test for the presence of esters or ethers in a chemical substance.
Combustion analysis is a method used in both organic chemistry and analytical chemistry to determine the elemental composition of a pure organic compound by combusting the sample under conditions where the resulting combustion products can be quantitatively analyzed. Once the number of moles of each combustion product has been determined the empirical formula or a partial empirical formula of the original compound can be calculated.
Mercury(II) nitrate is an inorganic compound with the chemical formula Hg(NO3)2. It is the mercury(II) salt of nitric acid HNO3. It contains mercury(II) cations Hg2+ and nitrate anions NO−3, and water of crystallization H2O in the case of a hydrous salt. Mercury(II) nitrate forms hydrates Hg(NO3)2·xH2O. Anhydrous and hydrous salts are colorless or white soluble crystalline solids that are occasionally used as a reagents. Mercury(II) nitrate is made by treating mercury with hot concentrated nitric acid. Neither anhydrous nor monohydrate has been confirmed by X-ray crystallography. The anhydrous material is more widely used.
The Zincke–Suhl reaction is a special case of a Friedel-Crafts alkylation and was first described by Theodor Zincke and Suhl in 1906. Unlike the traditional Friedel-Crafts reaction, the reduction of the phenyl ring leads to a higher energy final product that can be used as starting material in the dienol–benzene rearrangement, among other reactions.
Deoxygenation is a chemical reaction involving the removal of oxygen atoms from a molecule. The term also refers to the removal of molecular oxygen (O2) from gases and solvents, a step in air-free technique and gas purifiers. As applied to organic compounds, deoxygenation is a component of fuels production as well a type of reaction employed in organic synthesis, e.g. of pharmaceuticals.
The Milas hydroxylation is an organic reaction converting an alkene to a vicinal diol, and was developed by Nicholas A. Milas in the 1930s. The cis-diol is formed by reaction of alkenes with hydrogen peroxide and either ultraviolet light or a catalytic osmium tetroxide, vanadium pentoxide, or chromium trioxide.
The Béchamp reduction is a chemical reaction that converts aromatic nitro compounds to their corresponding anilines using iron as the reductant:
The Riemschneider thiocarbamate synthesis converts alkyl or aryl thiocyanates to thiocarbamates under acidic conditions, followed by hydrolysis with ice water. The reaction was discovered by the German chemist Randolph Riemschneider in 1951 as a more efficient method to produce thiocarbamates. Some references spell the name Riemenschneider.
Sanger–Black apparatus is a piece of chemical laboratory ware used for quantitative and semi-quantitative determination of arsenic element in the solution. It is constituted by glass bottle of volume ca. 30 mL, sealed with rubber stopper with one or two holes. Through one hole a thistle tube is inserted, almost reaching the bottom, for filling the bottle (what can be done also when the stopper is taken out – for semi-quantitative determination). The second, S-shaped tube is for outflow of the gases and joined by another rubber stopper to a bulg tube, with bulb containing pre-dried cotton as adsorbent, presumably intended for homogenizing the gas flow. A thin reagent paper, impregnated with mercury(II) chloride (nowadays replaced by mercury(II) bromide) or silver(I) nitrate, is placed in the open end of the bulb tube. If the semi-quantitative variant is to be performed, the paper is put in the (only) thistle tube – i. e., vertically, not horizontally. During the test ca. 3 g of Zn granules are placed into the bottle, just below the end of thistle tube, and then acid solution is added (ca. 15 mL; authors recommend that HCl is preferable to H2SO4). About 10 minutes are required to let H2 flow along the reagent paper, while this flow and moisture content inside it is stabilizing. Then the sample is introduced, and in case of sample solution containing arsenic the paper becomes more or less stained.
In organic chemistry, the Lombardo methylenation is a name reaction that allows for the methylenation of carbonyl compounds with the use of Lombardo's reagent, which is a mix of zinc, dibromomethane, and titanium tetrachloride.