Pyrrole is a heterocyclic aromatic organic compound, a five-membered ring with the formula C4H4NH. It is a colorless volatile liquid that darkens readily upon exposure to air. Substituted derivatives are also called pyrroles, e.g., N-methylpyrrole, C4H4NCH3. Porphobilinogen, a trisubstituted pyrrole, is the biosynthetic precursor to many natural products such as heme.
Pyrazine is a heterocyclic aromatic organic compound with the chemical formula C4H4N2. It is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. It is a "deliquescent crystal or wax-like solid with a pungent, sweet, corn-like, nutty odour".
Hydrazoic acid, also known as hydrogen azide or azoimide, is a compound with the chemical formula HN3. It is a colorless, volatile, and explosive liquid at room temperature and pressure. It is a compound of nitrogen and hydrogen, and is therefore a pnictogen hydride. It was first isolated in 1890 by Theodor Curtius. The acid has few applications, but its conjugate base, the azide ion, is useful in specialized processes.
The Bischler–Möhlau indole synthesis, also often referred to as "The Bischler Indole Synthesis," is a chemical reaction that forms a 2-aryl-indole from an α-bromo-acetophenone and excess aniline; it is named after August Bischler and Richard Möhlau .
Friedrich Karl Johannes Thiele was a German chemist and a prominent professor at several universities, including those in Munich and Strasbourg. He developed many laboratory techniques related to isolation of organic compounds. In 1907 he described a device for the accurate determination of melting points, since named Thiele tube after him.
The Curtius rearrangement, first defined by Theodor Curtius in 1885, is the thermal decomposition of an acyl azide to an isocyanate with loss of nitrogen gas. The isocyanate then undergoes attack by a variety of nucleophiles such as water, alcohols and amines, to yield a primary amine, carbamate or urea derivative respectively. Several reviews have been published.
The Reed reaction is a chemical reaction that utilizes light to oxidize hydrocarbons to alkylsulfonyl chlorides. This reaction is employed in modifying polyethylene to give chlorosulfonated polyethylene (CSPE), which noted for its toughness.
Diphenylchloroarsine (DA) is the organoarsenic compound with the formula (C6H5)2AsCl. It is highly toxic and was once used in chemical warfare. It is also an intermediate in the preparation of other organoarsenic compounds. The molecule consists of a pyramidal As(III) center attached to two phenyl rings and one chloride. It was also known as sneezing oil during World War I by the Allies.
Ethyl diazoacetate (N=N=CHC(O)OC2H5) is a diazo compound and a reagent in organic chemistry. It was discovered by Theodor Curtius in 1883. The compound can be prepared by reaction of the ethyl ester of glycine with sodium nitrite and sodium acetate in water.
Organomercury refers to the group of organometallic compounds that contain mercury. Typically the Hg–C bond is stable toward air and moisture but sensitive to light. Important organomercury compounds are the methylmercury(II) cation, CH3Hg+; ethylmercury(II) cation, C2H5Hg+; dimethylmercury, (CH3)2Hg, diethylmercury and merbromin ("Mercurochrome"). Thiomersal is used as a preservative for vaccines and intravenous drugs.
The Wolffenstein–Böters reaction is an organic reaction converting benzene to picric acid by a mixture of aqueous nitric acid and mercury(II) nitrate.
The Schmidt reaction is an organic reaction in which an azide reacts with a carbonyl derivative, usually a aldehyde, ketone, or carboxylic acid, under acidic conditions to give an amine or amide, with expulsion of nitrogen. It is named after Karl Friedrich Schmidt (1887–1971), who first reported it in 1924 by successfully converting benzophenone and hydrazoic acid to benzanilide. Surprisingly, the intramolecular reaction was not reported until 1991 but has become important in the synthesis of natural products.
Ludwig Gattermann was a German chemist who contributed significantly to both organic and inorganic chemistry.
Phthalonitrile is an organic compound with the formula C6H4(CN)2, which is an off-white crystal solid at room temperature. It is a derivative of benzene, containing two adjacent nitrile groups. The compound has low solubility in water but is soluble in common organic solvents. The compound is used as a precursor to phthalocyanine and other pigments, fluorescent brighteners, and photographic sensitizers.
Ammonium azide is the chemical compound with the formula [NH4]N3, being the salt of ammonia and hydrazoic acid. Like other inorganic azides, this colourless crystalline salt is a powerful explosive, although it has a remarkably low sensitivity. [NH4]N3 is physiologically active and inhalation of small amounts causes headaches and palpitations. It was first obtained by Theodor Curtius in 1890, along with other azides.
Friedrich Oskar Giesel was a German organic chemist. During his work in a quinine factory in the late 1890s, he started to work on the at-that-time-new field of radiochemistry and started the production of radium. In the period between 1902 and 1904, he was able to isolate a new element emanium. In a now controversially reviewed process, it was stated that emanium is identical to actinium, which was discovered by André-Louis Debierne in 1899.
Chlorine azide is an inorganic compound that was discovered in 1908 by Friedrich Raschig. Concentrated ClN3 is notoriously unstable and may spontaneously detonate at any temperature.
Phenylsodium C6H5Na is an organosodium compound. Solid phenylsodium was first isolated by Nef in 1903. Although the behavior of phenylsodium and phenyl magnesium bromide are similar, the organosodium compound is very rarely used.
The Buchner–Curtius–Schlotterbeck reaction is the reaction of aldehydes or ketones with aliphatic diazoalkanes to form homologated ketones. It was first described by Eduard Buchner and Theodor Curtius in 1885 and later by Fritz Schlotterbeck in 1907. Two German chemists also preceded Schlotterbeck in discovery of the reaction, Hans von Pechmann in 1895 and Viktor Meyer in 1905. The reaction has since been extended to the synthesis of β-keto esters from the condensation between aldehydes and diazo esters. The general reaction scheme is as follows:
