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Diazene
Diimide, also called diazene or diimine, is a compound having the formula HN=NH. It exists as two geometric isomers, ''E'' (''trans'') and ''Z'' (''cis''). The term diazene is more common for organic derivatives of diimide. Thus, azobenzene is an example of an organic diazene. Synthesis A traditional route to diimide involves oxidation of hydrazine with hydrogen peroxide or air. : Alternatively the hydrolysis of diethyl azodicarboxylate or azodicarbonamide affords diimide: : Nowadays, diimide is generated by thermal decomposition of 2,4,6‐triisopropylbenzenesulfonylhydrazide. Because of its instability, diimide is generated and used ''in-situ''. A mixture of both the ''cis'' (''Z-'') and ''trans'' (''E-'') isomers is produced. Both isomers are unstable, and they undergo a slow interconversion. The ''trans'' isomer is more stable, but the ''cis'' isomer is the one that reacts with unsaturated substrates, therefore the equilibrium between them shifts towards the ''cis'' isomer du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isodiazene
In organic chemistry, an isodiazene, also known by the incorrectly constructed (but commonly used) name 1,1-diazene or systematic name diazanylidene, is an organic derivative of the parent isodiazene (H2N+=N–, also called 1,1-diimide) with general formula R1R2N+=N–. The functional group has two major resonance forms, a diazen-2-ium-1-ide form, and an aminonitrene form: Although isodiazenes are formally Isoelectronicity, isoelectronic with Carbonyl compounds, ketones and aldehydes, the reactivity of this exotic functional group is very different. They are generally prepared by oxidation of the hydrazine (R2N–NH2), reduction of the 1,1-diazene oxide (R2N–N=O), 1,1-elimination of MX from R2N–NMX (M = Na, K; X = SO2Ar), or treatment of secondary amines with Angeli's salt, Na2N2O3, in the presence of acid. Isodiazenes participate in cycloaddition reactions with alkenes to generate ''N''-aminoaziridines. In the absence of other reactants, they undergo reactions in which N2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azodicarbonamide
Azodicarbonamide, ADCA, ACA, ADA, or azo(''bis'')formamide, is a chemical compound with the molecular formula . It is a yellow to orange-red, odorless, crystalline powder. It is sometimes called "the yoga mat chemical" because of widespread use in foamed plastics. It was first described by John Bryden in 1959. Synthesis It is prepared in two steps via treatment of urea with hydrazine to form biurea, as described in this idealized equation: : Oxidation of biurea with gaseous chlorine yields azodicarbonamide: : Applications Blowing agent The principal use of azodicarbonamide is in the production of foamed plastics as a blowing agent. The thermal decomposition of azodicarbonamide produces nitrogen, carbon monoxide, carbon dioxide, and ammonia gases, which are trapped in the polymer as bubbles to form a foamed article. Azodicarbonamide is used in plastics, synthetic leather, and other industries and can be pure or modified. Modification affects the reaction temperatures. Pure azo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrazene
Tetrazene is a chemical compound with the molecular formula H2NN=NNH2. It is a colorless explosive material. An analogue is the organosilicon derivative (tms)2NN=NN(tms)2 where tms is trimethylsilyl. Isomeric with tetrazine is ammonium azide. Tetrazene explosive, commonly known simply as tetrazene, is used for sensitization of priming compositions. Properties Tetrazene has eleven isomers. The most stable of these is the straight-chain 2-tetrazene (H2N-N=N-NH2), having a standard heat of formation at 301.3 kJ/mol. The eleven isomers can be arranged into three groups: straight-chain tetrazenes, four-membered cyclotetrazane, and three-membered cyclotriazanes. Each straight-chain tetrazene isomer possesses one N=N double bond and two N-N single bonds. Tautomerizations do occur between the isomers. The ionic compound ammonium azide is also a constitutional isomer of tetrazene. Organometallic derivatives A variety of coordination complex A coordination complex is a chemical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Azodicarboxylate
Diethyl azodicarboxylate, conventionally abbreviated as DEAD and sometimes as DEADCAT, is an organic compound with the structural formula . Its molecular structure consists of a central azo compound, azo functional group, RN=NR, flanked by two ethyl ester groups. This orange-red liquid is a valuable reagent but also quite dangerous and explodes upon heating. Therefore, commercial shipment of pure diethyl azodicarboxylate is prohibited in the United States and is carried out either in solution or on polystyrene particles. DEAD is an aza-Diels–Alder reaction, dienophile and an efficient dehydrogenating agent, converting Alcohol (chemistry), alcohols to aldehydes, thiols to disulfides and hydrazo groups to Azo compound, azo groups; it is also a good electron acceptor. While DEAD is used in numerous chemical reactions it is mostly known as a key component of the Mitsunobu reaction, a common strategy for the preparation of an amine, azide, ether, thioether, or ester from the corresp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinitrogen Difluoride
Dinitrogen difluoride is a chemical compound with the formula . It is a gas at room temperature, and was first identified in 1952 as the thermal decomposition product of the fluorine azide (). It has the structure and exists in both ''cis'' and ''trans'' isomers, as typical for diimides. Isomers The ''cis'' isomer has C2v symmetry and the ''trans'' isomer has C2h symmetry. These isomers can interconvert, but the process is slow enough at low temperature that the two can separated by low-temperature fractionation. The ''trans'' isomer is less thermodynamically stable but can be stored in glass vessels. The ''cis'' isomer attacks glass over a time scale of about 2 weeks to form silicon tetrafluoride and nitrous oxide: : Preparation Most preparations of dinitrogen difluoride give mixtures of the two isomers, but they can be prepared independently. An aqueous method involves ''N'',''N''-difluorourea with concentrated potassium hydroxide. This gives a 40% yield with three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly hazardous unless handled in solution as, for example, hydrazine hydrate (). Hydrazine is mainly used as a foaming agent in preparing Polymeric foam, polymer foams, but applications also include its uses as a precursor (chemistry), precursor to pharmaceuticals and agrochemicals, as well as a long-term storable propellant for in-outer space, space spacecraft propulsion. Additionally, hydrazine is used in various rocket propellant, rocket fuels and to prepare the gas precursors used in airbags. Hydrazine is used within both nuclear and conventional electrical power plant steam cycles as an oxygen scavenger to control concentrations of dissolved oxygen in an effort to reduce corrosion. , approximately 120,000 tons of hydrazine hydrate (corresponding to a 64% solution of hydrazine in water by weight) we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triazane
Triazane is an inorganic compound with the chemical formula or . Triazane is the third simplest acyclic azane after ammonia and hydrazine. It can be synthesized from hydrazine but is unstable and cannot be isolated in the free base form, only as salt forms such as triazanium sulfate. Attempts to convert triazanium salts to the free base release only diazene and ammonia. Triazane was first synthesized as a 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 formal donation of one or more of the ligand's el ... of the silver complex ion: tris(μ2-triazane-κ2''N''1,''N''3)disilver(2+). Triazane has also been synthesized in electron-irradiated ammonia ices and detected as a stable gas-phase product after sublimation.Förstel, Maksyutenko, Jones, Sun, Chen, Chang, & Kaiser. "Detection of the Elusive Triazane Molecule () in the Ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triazene
Triazene is an unsaturated inorganic compound having the chemical formula N3 H3. It has one double bond and is the second-simplest member of the azene class of hydronitrogen compounds, after diimide. Triazenes are a class of organic compounds containing the functional group −N(H)−N=N−. Triazene, possibly along with its isomer triimide (HNNHNH), has been synthesized in electron-irradiated ices of ammonia and ammonia/dinitrogen and detected in the gas phase after sublimation. References External links *IUPAC Gold Book The International Union of Pure and Applied Chemistry (IUPAC) publishes many books which contain its complete list of definitions. The definitions are divided initially into seven IUPAC Colour Books: Gold, Green, Blue, Purple, Orange, White, and R ...br>definition {{Hydrides by group Nitrogen hydrides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinitrogen Difluoride
Dinitrogen difluoride is a chemical compound with the formula . It is a gas at room temperature, and was first identified in 1952 as the thermal decomposition product of the fluorine azide (). It has the structure and exists in both ''cis'' and ''trans'' isomers, as typical for diimides. Isomers The ''cis'' isomer has C2v symmetry and the ''trans'' isomer has C2h symmetry. These isomers can interconvert, but the process is slow enough at low temperature that the two can separated by low-temperature fractionation. The ''trans'' isomer is less thermodynamically stable but can be stored in glass vessels. The ''cis'' isomer attacks glass over a time scale of about 2 weeks to form silicon tetrafluoride and nitrous oxide: : Preparation Most preparations of dinitrogen difluoride give mixtures of the two isomers, but they can be prepared independently. An aqueous method involves ''N'',''N''-difluorourea with concentrated potassium hydroxide. This gives a 40% yield with three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiol
In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl group, or a sulfanyl group. Thiols are the sulfur analogue of alcohols (that is, sulfur takes the place of oxygen in the hydroxyl () group of an alcohol), and the word is a blend of "''thio-''" with "alcohol". Many thiols have strong odors resembling that of garlic, cabbage or rotten eggs. Thiols are used as odorants to assist in the detection of natural gas (which in pure form is odorless), and the smell of natural gas is due to the smell of the thiol used as the odorant. Nomenclature Thiols are sometimes referred to as mercaptans () or mercapto compounds, a term introduced in 1832 by William Christopher Zeise and is derived from the Latin ('capturing mercury')''Oxford American Dictionaries'' (Mac OS X Leopard). because the thiolate grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dication
A dication is any cation, of general formula X2+, formed by the removal of two electrons from a neutral species. Diatomic dications corresponding to stable neutral species (e.g. formed by removal of two electrons from H2) often decay quickly into two singly charged particles (H+), due to the loss of electrons in bonding molecular orbitals. Energy levels of diatomic dications can be studied with good resolution by measuring the yield of pairs of zero-kinetic-energy electrons from double photoionization of a molecule as a function of the photoionizing wavelength (threshold photoelectrons coincidence spectroscopy – TPEsCO). The dication is kinetically stable. An example of a stable diatomic dication which is not formed by oxidation of a neutral diatomic molecule is the dimercury dication . An example of a polyatomic dication is , formed by oxidation of S8 and unstable with respect to further oxidation over time to form SO2. Many organic dications can be detected in mass spectro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Bond Strength Order
Relative may refer to: General use *Kinship and family, the principle binding the most basic social units of society. If two people are connected by circumstances of birth, they are said to be ''relatives''. Philosophy *Relativism, the concept that points of view have no absolute truth or validity, having only relative, subjective value according to differences in perception and consideration, or relatively, as in the relative value of an object to a person * Relative value (philosophy) Economics *Relative value (economics) Popular culture Film and television * ''Relatively Speaking'' (1965 play), 1965 British play * ''Relatively Speaking'' (game show), late 1980s television game show * ''Everything's Relative'' (episode)#Yu-Gi-Oh! (Yu-Gi-Oh! Duel Monsters), 2000 Japanese anime ''Yu-Gi-Oh! Duel Monsters'' episode *'' Relative Values'', 2000 film based on the play of the same name. *''It's All Relative'', 2003-4 comedy television series *''Intelligence is Relative'', tag line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
