The nitrite ion has the chemical formula NO−
2. Nitrite is widely used throughout chemical and pharmaceutical industries. The nitrite anion is a pervasive intermediate in the nitrogen cycle in nature. The name nitrite also refers to organic compounds having the –ONO group, which are esters of nitrous acid.
Styphnic acid, or 2,4,6-trinitro-1,3-benzenediol, is a yellow astringent acid that forms hexagonal crystals. It is used in the manufacture of dyes, pigments, inks, medicines, and explosives such as lead styphnate. It is itself a low-sensitivity explosive, similar to picric acid, but explodes upon rapid heating.
The benzoin addition is an addition reaction involving two aldehydes. The reaction generally occurs between aromatic aldehydes or glyoxals, and results in formation of an acyloin. In the classic example, benzaldehyde is converted to benzoin.
The Fritsch–Buttenberg–Wiechell rearrangement, named for Paul Ernst Moritz Fritsch (1859–1913), Wilhelm Paul Buttenberg, and Heinrich G. Wiechell, is a chemical reaction whereby a 1,1-diaryl-2-bromo-alkene rearranges to a 1,2-diaryl-alkyne by reaction with a strong base such as an alkoxide.
Carl Dietrich Harries was a German chemist born in Luckenwalde, Brandenburg, Prussia. He received his doctorate in 1892. In 1900, he married Hertha von Siemens, daughter of the electrical genius Werner von Siemens, and the inventor of one of the earliest ozone generators. In 1904, he moved as full professor to the University of Kiel, where he remained until 1916. During that time he published numerous papers on ozonolysis. His major publication detailing ozonolysis was published in Liebigs Ann. Chem. 1905, 343, 311. Dissatisfied with academic life and having failed to obtain either of two positions at universities, he left academia to become director of research at Siemens and Halske. He died on 3 November 1923 of complications following surgery for cancer. He was buried at Stahnsdorf South-Western Cemetery near Berlin.
Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. These natural chemicals most likely contribute to plant defence against pests and diseases, and impart a characteristic bitter flavor property to cruciferous vegetables.
Wilhelm Rudolph Fittig was a German chemist. He discovered the pinacol coupling reaction, mesitylene, diacetyl and biphenyl. Fittig studied the action of sodium on ketones and hydrocarbons. He discovered the Fittig reaction or Wurtz–Fittig reaction for the synthesis of alkylbenzenes, he proposed a diketone structure for benzoquinone and isolated phenanthrene from coal tar. He discovered and synthesized the first lactones and investigated structures of piperine, naphthalene, and fluorene.
Crotonic acid ((2E)-but-2-enoic acid) is a short-chain unsaturated carboxylic acid described by the formula CH3CH=CHCO2H. The name crotonic acid was given because it was erroneously thought to be a saponification product of croton oil. It crystallizes as colorless needles from hot water. With a cis-alkene, Isocrotonic acid is an isomer of crotonic acid. Crotonic acid is soluble in water and many organic solvents. Its odor is similar to that of butyric acid.
The Lossen rearrangement is the conversion of a hydroxamate ester to an isocyanate. Typically O-acyl, sulfonyl, or phosphoryl O-derivative are employed. The isocyanate can be used further to generate ureas in the presence of amines or generate amines in the presence of H2O.
The Wurtz–Fittig reaction is the chemical reaction of an aryl halide, alkyl halides, and sodium metal to give substituted aromatic compounds. Following the work of Charles Adolphe Wurtz on the sodium-induced coupling of alkyl halides, Wilhelm Rudolph Fittig extended the approach to the coupling of an alkyl halide with an aryl halide. This modification of the Wurtz reaction is considered a separate process and is named for both scientists.
Myrosinase is a family of enzymes involved in plant defense against herbivores, specifically the mustard oil bomb. The three-dimensional structure has been elucidated and is available in the PDB.
Adolph Strecker was a German chemist who is remembered primarily for his work with amino acids.
Jakob Meisenheimer was a German chemist. He made numerous contributions to organic chemistry, the most famous being his proposed structure for a group of compounds now named Meisenheimer complex. He also proposed the mechanism of the Beckmann rearrangement. Later in his career, he reported the synthesis of the pyridine-N-oxide.
The Rosenmund–von Braun synthesis is an organic reaction in which an aryl halide reacts with cuprous cyanide to yield an aryl nitrile.
The Dimroth rearrangement is a rearrangement reaction taking place with certain 1,2,3-triazoles where endocyclic and exocyclic nitrogen atoms switch place. This organic reaction was discovered in 1909 by Otto Dimroth.
Methyl isocyanide or isocyanomethane is an organic compound and a member of the isocyanide family. This colorless liquid is isomeric and isoelectronic to methyl cyanide (acetonitrile), but its reactivity is very different. In contrast to the faintly sweet, ethereal odor of acetonitrile, the smell of methyl isocyanide, like that of other simple volatile isocyanides, is distinctly penetrating and vile. Methyl isocyanide is mainly used for making 5-membered heterocyclic rings. The C-N distance in methyl isocyanide is very short, 1.158 Å as is characteristic of isocyanides.
Conhydrine is a poisonous alkaloid found in poison hemlock in small quantities.
5-Aminotetrazole is an organic compound with the formula HN4CNH2. It is a white solid that can be obtained both in anhydrous and hydrated forms.
Cyameluric acid or 2,5,8-trihydroxy-s-heptazine is a chemical compound with formula C
6N
7O
3H
3, usually described as a heptazine molecule with the hydrogen atoms replaced by hydroxyl groups –OH; or any of its tautomers.
4-Hydroxybenzyl isothiocyanate is a naturally occurring isothiocyanate. It is formed as a degradation product of sinalbin from white mustard and is responsible for the pungent taste of mustard seeds.
