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Imidine
In chemistry imidines are a rare functional group, being the nitrogen analogues of anhydrides and imides. They were first reported by Adolf Pinner in 1883, but did not see significant investigation until the 1950s, when Patrick Linstead and John Arthur Elvidge developed a number of compounds. Imidines may be prepared in a modified Pinner reaction, by passing hydrogen chloride into an alcoholic solution of their corresponding di-nitriles (i.e. succinonitrile, glutaronitrile, adiponitrile) to give imino ethers which then condense when treated with ammonia. As a result, most structures are cyclic. The compounds are highly moisture sensitive and can be converted into imides upon exposure to water. See also *Amidine *Guanidines Guanidine is the compound with the formula HNC(NH2)2. It is a colourless solid that dissolves in polar solvents. It is a strong base that is used in the production of plastics and explosives. It is found in urine predominantly in patients experie ... Refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinner Reaction
The Pinner reaction refers to the acid catalysed reaction of a nitrile with an alcohol to form an imino ester salt (alkyl imidate 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: * With an excess of alcohol to form an orthoester * With ammonia or an amine to form an amidine (di-nitriles may form imidines, for instance succinimidine from succinonitrile) * With water to form an ester * With hydrogen sulfide to form a thionoester Commonly the Pinner salt itself is not isolated, with the reaction being continued to give the desired functional group (orthoester etc.) in one go. It should be appreciated that the Pinner reaction refers specifically to an acid catalyzed process, but that similar results can often be achieved using base catalysis. The two approaches can be complementary, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Acid Anhydride
An organic acid anhydride is an acid anhydride that is an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word ''acid'' in the name of the parent carboxylic acid by the word ''anhydride''. Thus, (CH3CO)2O is called ''acetic anhydride.'' Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known, whereby reaction occurs between two different carboxylic acids. Nomenclature of unsymmetrical acid anhydrides list the names of both of the reacted carboxylic acids before the word "anhydride" (for example, the dehydration reaction between benzoic acid and propanoic acid would yield "benzoic propanoic anhydride"). One or both acyl groups of an acid anhydride may also be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amidine
Amidines are organic compounds with the functional group RC(NR)NR2, where the R groups can be the same or different. They are the imine derivatives of amides (RC(O)NR2). The simplest amidine is formamidine, HC(=NH)NH2. Examples of amidines include: * DBU * diminazene * benzamidine * Pentamidine * Paranyline Preparation A common route to primary amidines is the Pinner reaction. Reaction of the nitrile with alcohol in the presence of acid gives an iminoether. Treatment of the resulting compound with ammonia then completes the conversion to the amidine. Instead of using a Bronsted acid, Lewis acids such as aluminium trichloride promote the direct amination of nitriles. They are also generated by amination of an imidoyl chloride. They are also prepared by the addition of organolithium reagents to diimines, followed by protonation or alkylation. Dimethylformamide acetal reacts with primary amines to give amidines: :Me2NC(H)(OMe)2 + RNH2 → Me2NC=NHR + 2 MeOH Properties and appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Imidine
Cycle, cycles, or cyclic may refer to: Anthropology and social sciences * Cyclic history, a theory of history * Cyclical theory, a theory of American political history associated with Arthur Schlesinger, Sr. * Social cycle, various cycles in social sciences ** Business cycle, the downward and upward movement of gross domestic product (GDP) around its ostensible, long-term growth trend Arts, entertainment, and media Films * ''Cycle'' (2008 film), a Malayalam film * ''Cycle'' (2017 film), a Marathi film Literature * ''Cycle'' (magazine), an American motorcycling enthusiast magazine * Literary cycle, a group of stories focused on common figures Music Musical terminology * Cycle (music), a set of musical pieces that belong together **Cyclic form, a technique of construction involving multiple sections or movements **Interval cycle, a collection of pitch classes generated from a sequence of the same interval class **Song cycle, individually complete songs designed to be performe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition. This enables systematic prediction of chemical reactions and behavior of chemical compounds and the design of chemical synthesis. The reactivity of a functional group can be modified by other functional groups nearby. Functional group interconversion can be used in retrosynthetic analysis to plan organic synthesis. A functional group is a group of atoms in a molecule with distinctive chemical properties, regardless of the other atoms in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by covalent bonds. For repeating units of polymers, functional groups attach to their nonpolar core of carbon atoms and thus add chemical character to carbon chains. Fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imide
In organic chemistry, an imide is a functional group consisting of two acyl groups bound to nitrogen. The compounds are structurally related to acid anhydrides, although imides are more resistant to hydrolysis. In terms of commercial applications, imides are best known as components of high-strength polymers, called polyimides. Inorganic imides are also known as solid state or gaseous compounds, and the imido group (=NH) can also act as a ligand. Nomenclature Most imides are cyclic compounds derived from dicarboxylic acids, and their names reflect the parent acid. Examples are succinimide, derived from succinic acid, and phthalimide, derived from phthalic acid. For imides derived from amines (as opposed to ammonia), the ''N''-substituent is indicated by a prefix. For example, N-ethylsuccinimide is derived from succinic acid and ethylamine. Isoimides are isomeric with normal imides and have the formula RC(O)OC(NR′)R″. They are often intermediates that convert to the more symmet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adolf Pinner
Adolf Pinner (August 31, 1842 – May 21, 1909) was a German chemist. Early life and education He was educated at the Jewish Theological Seminary of Breslau, Jewish Theological Seminary at Breslau and at the University of Berlin (Phd in Chemistry (Doctor der Chemie), 1867). In 1871 he became privat-docent at the University of Berlin. In 1873 he became assistant professor of chemistry at the University of Berlin, and in 1874 professor of chemistry at the veterinary college of that city. In 1884 he was appointed a member of the German patent office, and in the following year, of the technical division of the Prussian Department of Commerce. He has received the title "''Geheimer Regierungsrat''". Literary works Pinner contributed many essays to the professional scientific journal, journals, among which may be mentioned: * "''Darstellung und Untersuchung des Butylchlorals''," in "''Annalen der Chemie''", clxxix., and in "''Berichte der Deutschen Chemischen Gesellschaft''", 1870â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patrick Linstead
Sir (Reginald) Patrick Linstead CBE, DSc, HonDSc, DIC, HonFCGI, HonMIMM, FRS (28 August 1902, in London – 22 September 1966, in London) was an English chemist. Biography Patrick Linstead was born on 28 August 1902 in Southgate, London, the second son of Edward Flatman Linstead, advertising manager for Burroughs Wellcome, and Florence Evelyn, née Hester. After primary education in Southgate, Linstead attended the City of London School from the age of 11 to 17, where the science master, George H J Adlam, was a considerable influence. He joined Imperial College in 1920 and graduated three years later with first class honours, before continuing to a PhD in Sir Jocelyn Thorpe’s group. In 1929 Linstead was appointed as a demonstrator at Imperial, and later lecturer. In the following ten years he was awarded a DSc and three medals, and also married Aileen E E R Abbott. In 1938 he was appointed Professor Chemistry at the University of Sheffield, but the following year his wife died ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitriles
In organic chemistry, a nitrile is any organic compound that has a functional group. 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. Inorganic compounds containing the group are not called nitriles, but cyanides instead. Though both nitriles and cyanides can be derived from cyanide salts, most nitriles are not nearly as toxic. Structure and basic properties The N−C−C geometry is linear in nitriles, reflecting the sp hybridization of the triply bonded carbon. The C−N distance is short at 1.16 Å, consistent with a triple bond. Nitriles a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Succinonitrile
Succinonitrile, also butanedinitrile, is a nitrile, with the formula of C2H4(CN)2. It is a colorless waxy solid which melts at 58 °C. Succinonitrile is produced by the addition of hydrogen cyanide to acrylonitrile (hydrocyanation): :CH2=CHCN + HCN → NCCH2CH2CN Hydrogenation of succinonitrile yields putrescine (1,4-diaminobutane). See also * Malononitrile - A di-nitrile with 3 carbon atoms * Glutaronitrile - A di-nitrile with 5 carbon atoms * Adiponitrile Adiponitrile is an organic compound with the chemical formula (CH2)4(CN)2. This viscous, colourless dinitrile is an important precursor to the polymer nylon 66. In 2005, about one million tonnes of adiponitrile were produced.M. T. Musser, "Adip ... - A di-nitrile with 6 carbon atoms References External links WebBook page for C4H4N2 Alkanedinitriles {{Organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutaronitrile
Glutaronitrile, also pentanedinitrile, is a nitrile In organic chemistry, a nitrile is any organic compound that has a functional group. The prefix ''cyano-'' is used interchangeably with the term ''nitrile'' in industrial literature. Nitriles are found in many useful compounds, including met ..., with formula C3H6(CN)2. References External links WebBook page for glutaronitrile {{Organic-compound-stub Alkanedinitriles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adiponitrile
Adiponitrile is an organic compound with the chemical formula (CH2)4(CN)2. This viscous, colourless dinitrile is an important precursor to the polymer nylon 66. In 2005, about one million tonnes of adiponitrile were produced.M. T. Musser, "Adipic Acid" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Production Early methods Because of the industrial value of adiponitrile, many methods have been developed for its synthesis. Early industrial methods started from furfural and later by the chlorination of butadiene to give 1,4-dichloro-2-butene, which with sodium cyanide, converts to 3-hexenedinitrile, which in turn can be hydrogenated to adiponitrile: :ClCH2CH=CHCH2Cl + 2 NaCN → NCCH2CH=CHCH2CN + 2 NaCl :NCCH2CH=CHCH2CN + H2 → NC(CH2)4CN Adiponitrile has also been produced from adipic acid, by dehydration of the diamide, but this is rarely employed. Modern methods After patent application in 2004, the majority of adiponitrile is prepar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
