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Tetraamine
A polyamine is an organic compound having two or more amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. Most aromatic polyamines are crystalline solids at room temperature. Natural polyamines Low-molecular-weight linear polyamines are found in all forms of life. The principal examples are the triamine spermidine and the tetraamine spermine. They are structurally and biosynthetically related to the diamines putrescine and cadaverine. Polyamine metabolism is regulated by the activity of the enzyme ornithine decarboxylase (ODC). Polyamines are found in high concentrations in the mammalian brain. File:Spermidine-2D-skeletal.svg, spermidine File:Spermine.svg, spermine Synthetic polyamines Ethyleneamines are a commercially-important class of synthetic polyamines with ethylene ( linkages); global production capacity was estimated at 385,0 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethyleneamine
Ethyleneamines are a class of amine compounds containing ethylene (-CH2CH2-) linkages between amine groups. These compounds are generally colorless, low-viscosity liquids with a fishy amine odor. They are primarily used as building block chemicals and in epoxy resin curing agent chemistry. Production There are two main routes for the production of ethyleneamines, the reaction between ethylene dichloride and ammonia, and the reductive amination of monethanolamine. World capacity of ethyleneamines for the year 2001 was estimated to be 385,000 tonnes/year, with the majority comprising the ethylene dichloride route. In the ethylene dichloride route, the initial product of this reaction is ethylenediamine. In the presence of excess ethylene dichloride, the initial ethyleneamine is extended by one ethylene unit. The terminal alkyl chloride reacts with ammonia to give the amine, and the polyamine chain can be extended further in this fashion. Addition of a polyamine to the initial reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Group
In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of electrons. Amines can also exist as hetero cyclic compounds. Aniline is the simplest aromatic amine, consisting of a benzene ring bonded to an amino group. Amines are classified into three types: primary (1°), secondary (2°), and tertiary (3°) amines. Primary amines (1°) contain one alkyl or aryl substituent and have the general formula RNH2. Secondary amines (2°) have two alkyl or aryl groups attached to the nitrogen atom, with the general formula R2NH. Tertiary amines (3°) contain three substituent groups bonded to the nitrogen atom, and are represented by the formula R3N. The functional group present in primary amines is called the amino group. Classification of amines Amines can be classified according to the nature and number o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclen
Cyclen (1,4,7,10-tetraazacyclododecane) is an aza-crown ether with the formula (CH2CH2NH)4. It is a white solid. It forms Coordination complex, coordination complexes with metal cations and is used to synthesize the chelating agent DOTA (chelator), DOTA which has several medical applications. Being structurally simple, symmetrical, and polyfunctional, cyclen has been widely investigated. Synthesis Some syntheses exploit the Thorpe-Ingold effect to facilitate ring-formation. Illustrative is the reaction of the deprotonated tosylamides with ditosylates: :TsN(CH2CH2NTsNa)2 + TsN(CH2CH2OTs)2 → (TsNCH2CH2)4 The resulting macrocycle can be deprotected with strong acid. Base gives the tetramine. High dilution conditions result in a low reaction rate penalty and this disadvantage is removed in an alternative procedure starting from triethylenetetraamine and dithiooxamide to a amidine, bisamidine – also a bis(2-Imidazoline, imidazoline) – followed by organic reduction, reduc ... [...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] |
Hydrogen Sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is toxic, corrosive, and flammable. Trace amounts in ambient atmosphere have a characteristic foul odor of rotten eggs. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777. Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death. Despite this, the human body produces small amounts of this sulfide and its mineral salts, and uses it as a signalling molecule. Hydrogen sulfide is often produced from the microbial breakdown of organic matter in the absence of oxygen, such as in swamps and sewers; this process is commonly known as anaerobic digestio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formaldehyde
Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as aqueous solutions (formalin), which consists mainly of the hydrate CH2(OH)2. It is the simplest of the aldehydes (). As a precursor to many other materials and chemical compounds, in 2006 the global production of formaldehyde was estimated at 12 million tons per year. It is mainly used in the production of industrial resins, e.g., for particle board and coatings. Formaldehyde also occurs naturally. It is derived from the degradation of serine, dimethylglycine, and lipids. Demethylases act by converting N-methyl groups to formaldehyde. Formaldehyde is classified as a group 1 carcinogen and can cause respiratory and skin irritation upon exposure. Forms Formaldehyde is more complicated than many simple carbon compounds in that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3,5-triazinane
Triazinanes are a class of nitrogen-containing heterocycles.''Heterocyclic Chemistry'' T.L. Gilchrist 1985 (1997, The parent molecules' molecular formula is . They exist in three isomeric forms, 1,3,5-triazinanes being common. The triazinanes have six-membered cyclohexane-like ring but with three carbons replaced by nitrogens. Most commonly, the amines are tertiary. See also * 6-membered rings with one nitrogen atom: Piperidine * 6-membered rings with two nitrogen atoms: Diazinane ** Hexahydropyrimidine ** Hexahydropyridazine * Triazine * Borazine Borazine, also known as borazole, inorganic benzene, is an inorganic compound with the chemical formula B3H6N3. In this cyclic compound, the three BH units and three NH units alternate. The compound is isoelectronic and isostructural with benz ... (borazole) References {{Authority control Heterocyclic compounds with 1 ring Nitrogen heterocycles Six-membered rings Polyamines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aziridine
Aziridine is an organic compound consisting of the three-membered heterocycle . It is a colorless, toxic, volatile liquid that is of significant practical interest. Aziridine was discovered in 1888 by the chemist Siegmund Gabriel. Its derivatives, also referred to as aziridines, are of broader interest in medicinal chemistry. Structure The bond angles in aziridine are approximately 60°, considerably less than the normal hydrocarbon bond angle of 109.5°, which results in angle strain as in the comparable cyclopropane and ethylene oxide molecules. A banana bond model explains bonding in such compounds. Aziridine is less basic than acyclic aliphatic amines, with a pKa of 7.9 for the conjugate acid, due to increased s character of the nitrogen free electron pair. Angle strain in aziridine also increases the barrier to nitrogen inversion. This barrier height permits the isolation of separate ''invertomers'', for example the ''cis'' and ''trans'' invertomers of ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compound (chemistry), compounds, produces unique physical property, physical properties including toughness, high rubber elasticity, elasticity, viscoelasticity, and a tendency to form Amorphous solid, amorphous and crystallization of polymers, semicrystalline structures rath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylenimine
Polyethylenimine (PEI) or polyaziridine is a polymer with repeating units composed of the amine group and two carbon Aliphatic_compound, aliphatic ''CHCH'' spacers. Linear polyethyleneimines contain all Amines#Classification_of_amines, secondary amines, in contrast to branched PEIs which contain primary, secondary and tertiary amino groups. Totally branched, dendrimeric forms were also reported. PEI is produced on an industrial scale and finds many applications usually derived from its polyelectrolyte, polycationic character. Properties The linear PEI is a semi-crystalline solid at room temperature while branched PEI is a fully amorphous polymer existing as a liquid at all molecular weights. Linear polyethyleneimine is soluble in hot water, at low pH, in methanol, ethanol, or chloroform. It is insoluble in cold water, benzene, Diethyl ether, ethyl ether, and acetone. Linear polyethylenimine has a melting point of around 67 °C. Both linear and branched polyethylneimine c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,1,1-Tris(aminomethyl)ethane
1,1,1-Tris(aminomethyl)ethane (TAME) is an organic compound with the formula CHC(CHNH). It is a colorless liquid. It is classified as a polyamine tripodal ligand, i.e., capable of binding to metal ions through three sites and hence is a tridentate chelating ligand, occupying a face of the coordination polyhedron. Preparation TAME is synthesized by the Pd/C-catalyzed hydrogenation of 1,1,1-tris(azidomethyl)ethane. Although azides are potentially explosive, they are excellent and practical source of primary amines. The required tris(azidomethyl)ethane is obtained from the tri tosylate by salt metathesis using sodium azide. These two steps are: :3 NaN + CHC(CHOTs) → CHC(CHN) + 3 NaOTs :3 H + CHC(CHN) → CHC(CHNH) + 3 N Complexes of TAME The tripodal TAME ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
