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2,4,6-Trimethylpyridine
2,4,6-Trimethylpyridine (2,4,6-collidine) is an organic compound which belongs to the heterocycles (more precisely, heteroaromatics). It consists of a pyridine ring substituted with three methyl groups. It belongs to the substance group of the collidines, a group of six constitutional isomers. 2,4,6-trimethylpyridine is the most well-known isomer of this group. Properties The compound has a refractive index of 1.4959 (25 °C). Preparation 2,4,6-Trimethylpyridine was isolated from Dippel's oil in 1854. A synthesis can be carried out analogously to the Hantzsch's dihydropyridine synthesis from ethyl acetoacetate (as β-ketocarbonyl compound), acetaldehyde and ammonia in the ratio 2: 1: 1. Use By oxidation of the methyl groups with potassium permanganate collidinic acid is obtained. 2,4,6-Trimethylpyridine is used in organic syntheses (for example, for dehydrohalogenation), by binding the formed hydrogen halide In chemistry, hydrogen halides (hydrohalic acids when in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collidine
Collidine is the trivial name used to describe the chemical compounds which are Methyl group, trimethyl derivative (chemistry), derivatives of pyridine. Their chemical properties resemble those of pyridine, although the presence of the methyl groups may prohibit some of the more straightforward reactions. Collidine comes in several Isomer, isomers: *2,3,4-Collidine (2,3,4-trimethylpyridine) *2,3,5-Collidine (2,3,5-trimethylpyridine) *2,3,6-Collidine (2,3,6-trimethylpyridine) *2,4,5-Collidine (2,4,5-trimethylpyridine) *2,4,6-Collidine (2,4,6-trimethylpyridine) *3,4,5-Collidine (3,4,5-trimethylpyridine) All isomers share the molecular weight 121.18 g/mol and the chemical formula C8H11N. {{chemistry index Pyridines Amines Amine solvents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mole (unit)
The mole, symbol mol, is the unit of amount of substance in the International System of Units (SI). The quantity amount of substance is a measure of how many elementary entities of a given substance are in an object or sample. The mole is defined as containing exactly elementary entities. Depending on what the substance is, an elementary entity may be an atom, a molecule, an ion, an ion pair, or a subatomic particle such as an electron. For example, 10 moles of water (a chemical compound) and 10 moles of mercury (a chemical element), contain equal amounts of substance and the mercury contains exactly one atom for each molecule of the water, despite the two having different volumes and different masses. The number of elementary entities in one mole is known as the Avogadro number, which is the approximate number of nucleons (protons or neutrons) in one gram of ordinary matter. The previous definition of a mole was simply the number of elementary entities equal to that of 12 gram ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich August Pierer
Heinrich August Pierer, c.1850 Heinrich August Pierer (26 February 1794 in Altenburg – 12 May 1850, Altenburg) was a German lexicographer and publisher known particularly for his ''Universal-Lexikon der Vergangenheit und Gegenwart'', a multi-volume encyclopedic dictionary first published in 1835–6. It went through a number of editions, both during his lifetime and later. He was the son of publisher Johann Friedrich Pierer (de) (1767–1832). He studied medicine at the University of Jena, afterwards being involved in the Napoleonic Wars. He fought in the Battle of Leipzig, being wounded at the storming of Wachau, and later participated in the Battle of Waterloo The Battle of Waterloo was fought on Sunday 18 June 1815, near Waterloo, Belgium, Waterloo (at that time in the United Kingdom of the Netherlands, now in Belgium). A French army under the command of Napoleon was defeated by two of the armie .... Following the end of hostilities he worked as a schoolteacher i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Halide
In chemistry, hydrogen halides (hydrohalic acids when in the aqueous phase) are diatomic, inorganic compounds that function as Arrhenius acids. The formula is HX where X is one of the halogens: fluorine, chlorine, bromine, iodine, or astatine. All known hydrogen halides are gases at Standard Temperature and Pressure.The Acidity of the Hydrogen Halides. (2020, August 21). Retrieved May 5, 2021, from https://chem.libretexts.org/@go/page/3699 Vs. hydrohalic acids The hydrogen halides are diatomic molecules with no tendency to ionize in the gas phase (although liquified hydrogen fluoride is a polar solvent somewhat similar to water). Thus, chemists distinguish hydrogen chloride from hydrochloric acid. The former is a gas at room temperature that reacts with water to give the acid. Once the acid has formed, the diatomic molecule can be regenerated only with difficulty, but not by normal distillation. Commonly the names of the acid and the molecules are not clearly distinguished ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydrohalogenation
In chemistry, dehydrohalogenation is an elimination reaction which removes a hydrogen halide from a substrate. The reaction is usually associated with the synthesis of alkenes, but it has wider applications. Dehydrohalogenation from alkyl halides Traditionally, alkyl halides are substrates for dehydrohalogenations. The alkyl halide must be able to form an alkene, thus halides having no C–H bond on an adjacent carbon are not suitable substrates. Aryl halides are also unsuitable. Upon treatment with strong base, chlorobenzene dehydrohalogenates to give phenol via a benzyne intermediate. Base-promoted reactions to alkenes When treated with a strong base many alkyl chlorides convert to corresponding alkene. It is also called a β-elimination reaction and is a type of elimination reaction. Some prototypes are shown below: :\begin \ce\ &\ce \\ \ce\ &\ce \\ \ce\ &\ce \end Here ethyl chloride reacts with potassium hydroxide, typically in a solvent such as ethanol, giving ethylene. Li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Metals
''Synthetic Metals'' is a peer-reviewed scientific journal covering electronic polymers and electronic molecular materials. Abstracting and indexing ''Synthetic Metals'' is abstracted and indexed in the following services: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 3.266. It has published several highly cited papers (1 with ~1000 citations; 5 with >600 citations; 30 with >200 citations, according to Web of Science); most of them are devoted to conductive polymers (especially polyaniline) and one to optical properties of carbon nanotubes The optical properties of carbon nanotubes are highly relevant for materials science. The way those materials interact with electromagnetic radiation is unique in many respects, as evidenced by their peculiar absorption, photoluminescence (fl ... (see Kataura plot). References External links * Elsevier academic journals English-language journals Semi-monthly journals Academic jour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Permanganate
Potassium permanganate is an inorganic compound with the chemical formula KMnO4. It is a purplish-black crystalline salt, that dissolves in water as K+ and , an intensely pink to purple solution. Potassium permanganate is widely used in the chemical industry and laboratories as a strong oxidizing agent, and also as a medication for dermatitis, for cleaning wounds, and general disinfection. It is on the World Health Organization's List of Essential Medicines. In 2000, worldwide production was estimated at 30,000 tonnes. Properties Potassium permanganate is the potassium salt of the tetrahedral transition metal oxo complex permanganate, in which four O2- ligands are bound to a manganese(VII) center. Structure KMnO4 forms orthorhombic crystals with constants: ''a'' = 910.5 pm, ''b'' = 572.0 pm, ''c'' = 742.5 pm. The overall motif is similar to that for barium sulfate, with which it forms solid solutions. In the solid (as in solution), each MnO4− centre is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to 45% of the world's food and fertilizers. Around 70% of ammonia is used to make fertilisers in various forms and composition, such as urea and Diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products. It is mainly collected by downward displacement of both air and water. Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body. The International Agency for Research on Cancer (IARC) has listed acetaldehyde as a Group 1 carcinogen. Acetaldehyde is "one of the mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berichte Der Deutschen Chemischen Gesellschaft
''Chemische Berichte'' (usually abbreviated as ''Ber.'' or ''Chem. Ber.'') was a German-language scientific journal of all disciplines of chemistry founded in 1868. It was one of the oldest scientific journals in chemistry, until it merged with ''Recueil des Travaux Chimiques des Pays-Bas'' to form ''Chemische Berichte/Recueil'' in 1997. ''Chemische Berichte/Recueil'' was then merged with other European journals in 1998 to form ''European Journal of Inorganic Chemistry''. History Founded in 1868 as ''Berichte der Deutschen Chemischen Gesellschaft'' (, CODEN BDCGAS), it operated under this title until 1928 (Vol. 61). The journal was then split into: * ''Berichte der Deutschen Chemischen Gesellschaft, A: Vereins-Nachrichten'' (, CODEN BDCAAS), and * ''Berichte der Deutschen Chemischen Gesellschaft, B: Abhandlungen'' (, CODEN BDCBAD). Vol. 78 and 79 (1945–1946) were omitted and not published due to World War II. The journal was renamed ''Chemische Berichte'' (, CODEN CHBEAM) in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dippel's Oil
Dippel's oil (sometimes referred to as bone oil) is a nitrogenous by-product of the destructive distillation of bones. A dark, viscous, tar-like liquid with an unpleasant smell, it is named after its inventor, Johann Konrad Dippel. The oil consists mostly of aliphatic chains, with nitrogen functionalities and includes species such as pyrroles, pyridines and nitriles, as well as other nitrogenous compounds. Dippel's oil had a number of uses which are now mostly obsolete. Its primary use was as an animal and insect repellent. It saw limited use as a chemical warfare harassing agent during the desert campaign of World War II. The oil was used to render wells undrinkable and thus deny their use to the enemy. By not being lethal, the oil was claimed to not be in breach of the Geneva Protocol. See also * Neatsfoot oil, another bone-derived oil * Bone char Bone char ( lat, carbo animalis) is a porous, black, granular material produced by charring animal bones. Its composition vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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