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2,2,6,6-Tetramethylpiperidine
2,2,6,6-Tetramethylpiperidine, abbreviated TMP, HTMP, or TMPH, is an organic compound of the amine class. In appearance, it is a colorless liquid and has a "fishy", amine-like odor. This amine is used in chemistry as a hindered base ( hindered amine). Although TMP finds limited use per se, its derivatives are a mainstay of hindered amine light stabilizers. TMP is the starting material for an even stronger base, lithium tetramethylpiperidide and the radical species TEMPO. Another non-nucleophilic base is N,N-diisopropylethylamine. Its aqueous p''K''aH (conjugate acid dissociation constant, a measure of basicity) is 11.07 at 25 °C, while its p''K''a (acid dissociation constant, a measure of acidity) is approximately 37. Preparation Many routes for the synthesis of TMP have been reported. One method starts with a conjugate addition reaction of ammonia to phorone. The intermediate triacetone amine is then reduced in a Wolff-Kishner reaction. See also * 2,6-Dimethylpi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triacetone Amine
Triacetonamine is an organic compound with the formula OC(CH2CMe2)2NH (where Me = CH3). It is a colorless or white solid that melts near room temperature. The compound is an intermediate in the preparation of 2,2,6,6-Tetramethylpiperidine, 2,2,6,6-tetramethylpiperidine, a sterically hindered base and precursor to the reagent called TEMPO. Triacetonamine is formed by the poly-aldol condensation of acetone in the presence of ammonia and calcium chloride: :3 (CH3)2CO + NH3 → OC(CH2CMe2)2NH + 2 H2O Reductive amination of triacetonamine gives 4-Amino-2,2,6,6-tetramethylpiperidine, 4-amino-2,2,6,6-tetramethylpiperidine. It is primarily used as a stabilizer for plastics, typically via its conversion to number of hindered amine light stabilizers, but also finds use as a chemical feedstock. It is used to prepare the steric hindrance, hindered amine 2,2,6,6-Tetramethylpiperidine, 2,2,6,6-tetramethylpiperidine, CH2[CH2C(CH3)2]2NH, as well as the radical oxidizer 4-Hydroxy-TEMPO.{ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TMP Synthesis
TMP may refer to: Arts and media * Tickle Me Pink, a rock band from Colorado, US (2005–2011) * Tiny Moving Parts, an emo band from Minnesota, US * Tom Malone Prize, an Australian glass art prize * Tsukuyomi -Moon Phase-, a 2000–2008 anime series * '' Star Trek: The Motion Picture'', a 1979 film Businesses and organisations * TMP Worldwide Advertising and Communications * Te Māngai Pāho, a Māori broadcasting funding agency * Trans Metro Pasundan in Bandung, Indonesia * Tipra Motha Party, an Indian political party * Todd McFarlane Productions * Toyota Motor Philippines Cartography * Theban Mapping Project, of archaeologic sites * Transverse Mercator projection Chemicals * 2,2,6,6-Tetramethylpiperidine, an organic chemistry reagent * Thymidine monophosphate, a nucleotide * Trimethoprim, an antibiotic * Trimethyl phosphate, a solvent * Trimethylolpropane, a precursor to polymers Computing * Tab Mix Plus, a Mozilla Firefox extension * Template metaprogramming * .tmp, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N,N-Diisopropylethylamine
''N'',''N''-Diisopropylethylamine, or Hünig's base, is an organic compound that is a tertiary amine. It is named after the German chemist . It is used in organic chemistry as a non-nucleophilic base. It is commonly abbreviated as DIPEA, DIEA, or ''i''-Pr2NEt. Structure DIPEA consists of a central nitrogen atom that is bonded to an ethyl group and two isopropyl groups. A lone pair of electrons resides on the nitrogen atom, which can react with electrophiles. However, the three alkyl groups on the nitrogen atom create steric hindrance, so only small electrophiles such as Hydrogen ion, protons can react with the nitrogen lone pair. Occurrence and preparation DIPEA is commercially available. It is traditionally prepared by the alkylation of diisopropylamine with diethyl sulfate. Pure DIPEA exists as a colorless liquid, although commercial samples can be slightly yellow. If necessary, the compound can be purified by distillation from potassium hydroxide or calcium hydride. Use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. It is widely used in fertilizers, refrigerants, explosives, cleaning agents, and is a precursor for numeous chemicals. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers. Around 70% of ammonia produced industrially 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 chemicals. In many countries, it is classified as an List of extremely hazardous substances, extremely hazardous substance. Ammonia is toxic, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperidines
Piperidine is an organic compound with the molecular formula (CH2)5NH. This heterocyclic compound, heterocyclic amine consists of a six-membered ring containing five methylene bridges (–CH2–) and one amine bridge (–NH–). It is a colorless liquid with an odor described as objectionable, typical of amines. The name comes from the genus name ''Piper (genus), Piper'', which is the Latin word for Black pepper, pepper. Although piperidine is a common organic compound, it is best known as a representative structure element within many pharmaceuticals and alkaloids, such as natural-occurring Solenopsin, solenopsins. Production Piperidine was first reported in 1850 by the Scottish chemist Thomas Anderson (chemist), Thomas Anderson and again, independently, in 1852 by the French chemist Auguste André Thomas Cahours, Auguste Cahours, who named it. Both of them obtained piperidine by reacting piperine with nitric acid. Industrially, piperidine is produced by the hydrogenation of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Syntheses
''Organic Syntheses'' is a peer-reviewed scientific journal that was established in 1921. It publishes detailed and checked procedures for the synthesis of organic compounds. A unique feature of the review process is that all of the data and experiments reported in an article must be successfully repeated in the laboratory of a member of the editorial board as a check for reproducibility prior to publication. The journal is published by Organic Syntheses, Inc., a non-profit corporation. An annual print version is published by John Wiley & Sons on behalf of Organic Syntheses, Inc. History Prior to World War I, work on synthetic organic chemistry in the United States had been quite limited, and most of the reagents used in laboratories had to be imported from Europe. When export stoppages and trade embargoes cut off this source, Clarence Derick, a professor of chemistry at University of Illinois at Urbana-Champaign, began an effort to synthesize these needed chemicals in industri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pempidine
Pempidine is a nicotinic antagonist drug, first reported in 1958 by two research groups working independently, and introduced as an oral treatment for hypertension. Pharmacology Reports on the "classical" pharmacology of pempidine have been published. The Spinks group, at ICI, compared pempidine, its ''N''-ethyl analogue, and mecamylamine in considerable detail, with additional data related to several structurally simpler compounds. Toxicology LD50 for the HCl salt of pempidine in mice: 74 mg/kg (intravenous); 125 mg/kg (intraperitoneal); 413 mg/kg (oral). Chemistry Pempidine is an aliphatic, sterically hindered, cyclic, tertiary amine, which is a weak base: in its protonated form it has a p''K''a of 11.25. Pempidine is a liquid with a boiling point of 187–188 °C and a density of 0.858 g/cm3. Two early syntheses of this compound are those of Leonard and Hauck, and Hall. These are very similar in principle: Leonard and Hauck reacted phorone with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,6-Dimethylpiperidine
2,6-Dimethylpiperidines are chemical compounds with the formula C5H8(CH3)2NH. Three stereoisomers exist: the achiral (''R'',''S'')-isomer and the Chirality (chemistry), chiral (''R'',''R'')/(''S'',''S'') enantiomeric pair. Dimethylpiperidines are derivatives of the heterocycle piperidine, wherein two hydrogen atoms are replaced by methyl groups. The 2,6-dimethylpiperidines are prepared by reduction of 2,6-dimethylpyridine (2,6-lutidine). The achiral isomer is the predominant isomer produced in this reaction. The 2,6-dimethylpiperidines are of interest for their conformational properties. The (''R'',''S'')-isomer exists largely in the chair conformation with equatorial methyl groups. The (''R'',''R'')/(''S'',''S'')-isomers are attractive chiral secondary amine building blocks.Einhorn, J.; Einhorn, C.; Ratajczak, F.; Durif, A.; Averbuch, M.-T. and Pierre, J.-L., "Synthesis and resolution of a chiral analog of 2,2,6,6-tetramethylpiperidine and of its corresponding nitroxide", Tetr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phorone
Phorone, or diisopropylidene acetone, is a yellow crystalline substance with a geranium odor, with formula or . Preparation It was first obtained in 1837 in impure form by the French chemist Auguste Laurent, who called it "camphoryle". In 1849, the French chemist Charles Frédéric Gerhardt and his student Jean Pierre Liès-Bodart prepared it in a pure state and named it "phorone". On both occasions it was produced by ketonization through the dry distillation of the calcium salt of camphoric acid. : It is now typically obtained by the acid-catalysed twofold aldol condensation of three molecules of acetone. Mesityl oxide is obtained as an intermediate and can be isolated. Crude phorone can be purified by repeated recrystallization from ethanol or ether, in which it is soluble. Reactions Phorone can condense with ammonia to form triacetone amine. See also *Isophorone Isophorone is an Alpha-beta Unsaturated carbonyl compounds, α,β-unsaturated cyclic ketone. It is a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthesis (journal)
''Synthesis'' is a scientific journal published from 1969 to the present day by Thieme. Its stated purpose is the "advancement of the science of synthetic chemistry". From August 2006, selected articles are offered free of charge. The impact factor of this journal is 2.867 (2018).Journal Citation Reports, 2018 References Chemistry journals English-language journals Thieme academic journals {{chem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
