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Cyanamide
Cyanamide is an organic compound with the formula C N2 H2. This white solid is widely used in agriculture and the production of pharmaceuticals and other organic compounds. It is also used as an alcohol-deterrent drug. The molecule features a nitrile group attached to an amino group. Derivatives of this compound are also referred to as cyanamides, the most common being calcium cyanamide (CaCN2). Tautomers and self-condensations Containing both a nucleophilic and electrophilic site within the same molecule, cyanamide undergoes various reactions with itself. Cyanamide exists as two tautomers, one with the connectivity N≡C–NH2 and the other with the formula HN=C=NH ("carbodiimide" tautomer). The N≡C–NH2 form dominates, but in a few reactions (e.g. silylation) the diimide form appears to be important. Cyanamide dimerizes to give 2-cyanoguanidine (dicyandiamide). This dimerization is disfavored by acids and is inhibited by low temperatures. The cyclic trimer is called mela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Cyanamide
Calcium cyanamide is the inorganic compound with the formula CaCN2. It is the calcium salt of the cyanamide () anion. This chemical is used as fertilizer and is commercially known as nitrolime. It was first synthesized in 1898 by Adolph Frank and Nikodem Caro (Frank–Caro process). History In their search for a new process for producing cyanides for cyanide leaching of gold, Frank and Caro discovered the ability of alkaline earth carbides to absorb atmospheric nitrogen at high temperatures. Fritz Rothe, a colleague of Frank and Caro, succeeded in 1898 in overcoming problems with the use of calcium carbide and clarified that at around 1,100 °C not calcium cyanide but calcium cyanamide is formed in the reaction. In fact, the initial target product sodium cyanide can also be obtained from calcium cyanamide by melting it with sodium chloride in the presence of carbon: : CaCN2 + 2 NaCl + C → 2 NaCN + CaCl2 Frank and Caro developed this reaction for a large-scale, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Carbide
Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of Ca C2. Its main use industrially is in the production of acetylene and calcium cyanamide. The pure material is colorless, while pieces of technical-grade calcium carbide are grey or brown and consist of about 80–85% of CaC2 (the rest is CaO (calcium oxide), Ca3P2 ( calcium phosphide), CaS ( calcium sulfide), Ca3N2 (calcium nitride), SiC (silicon carbide), etc.). In the presence of trace moisture, technical-grade calcium carbide emits an unpleasant odor reminiscent of garlic. Applications of calcium carbide include manufacture of acetylene gas, generation of acetylene in carbide lamps, manufacture of chemicals for fertilizer, and steelmaking. Production Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately . This is an endothermic reaction requiring per mole and high temperatures to drive off the carbon monoxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Cyanoguanidine
2-Cyanoguanidine is a nitrile derived from guanidine. It is a dimer of cyanamide, from which it can be prepared. 2-Cyanoguanidine is a colourless solid that is soluble in water, acetone, and alcohol, but not nonpolar organic solvents. Production and use 2-Cyanoguanidine is produced by treating cyanamide with base. It is produced in soil by decomposition of cyanamide. A variety of useful compounds are produced from 2-cyanoguanidine, guanidines and melamine. For example, acetoguanamine and benzoguanamine are prepared by condensation of cyanoguanidine with the nitrile: :(H2N)2C=NCN + RCN → (CNH2)2(CR)N3 Cyanoguanidine is also used as a slow fertilizer. Formerly, it was used as a fuel in some explosives. It is used in the adhesive industry as a curing agent for epoxy resins. Chemistry Two tautomeric forms exist, differing in the protonation and bonding of the nitrogen to which the nitrile group is attached. : 2-Cyanoguanidine can also exist in a zwitterionic form via a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melamine
Melamine is an organic compound with the formula C3H6N6. This white solid is a trimer of cyanamide, with a 1,3,5-triazine skeleton. Like cyanamide, it contains 67% nitrogen by mass, and its derivatives have fire retardant properties due to its release of nitrogen gas when burned or charred. Melamine can be combined with formaldehyde and other agents to produce melamine resins. Such resins are characteristically durable thermosetting plastic used in high pressure decorative laminates such as Formica, melamine dinnerware, laminate flooring, and dry erase boards. Melamine foam is used as insulation, soundproofing material and in polymeric cleaning products, such as Magic Eraser. Melamine was once illegally added to baby formula in China, in order to increase the apparent protein content. Ingestion of melamine may lead to reproductive damage, or bladder or kidney stones, and bladder cancer. It is also an irritant when inhaled or in contact with the skin or eyes. The Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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. Nitril ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexazinone
Hexazinone is an organic compound that is used as a broad spectrum herbicide. It is a colorless solid. It exhibits some solubility in water but is highly soluble in most organic solvents except alkanes. A member of the triazine class herbicides, it is manufactured by DuPont and sold under the trade name Velpar. It functions by inhibiting photosynthesis and thus is a nonselective herbicide. It is used to control grasses, broadleaf, and woody plants. In the United States approximately 33% is used on alfalfa, 31% in forestry, 29% in industrial areas, 4% on rangeland and pastures, and < 2% on sugarcane. Hexazinone is a pervasive groundwater contaminant. Use of hexazinone causes groundwater to be at high risk of contamination due to the high leaching potential it exhibits. History Hexazinone is widely used as a herbicide. It is a non-selective herbicide from the triazine family. It is used among a broad range of places. It is used to control weeds within al ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenourea
Selenourea is the organoselenium compound with the formula SeC(NH2)2. It is a white solid. This compound features a rare example of a stable, unhindered carbon-selenium double bond. The compound is used in the synthesis of selenium heterocycles. Compared to urea, the oxo-analog of selenourea, few studies have been done on the compound due to the instability and toxicity of selenium compounds. Selenourea is toxic if inhaled or consumed. Synthesis The compound was first synthesized in 1884 by Auguste Verneuil by the reaction of hydrogen selenide and cyanamide: :H2Se + NCNH2 → SeC(NH2)2 While this reaction has even found use in industrial synthesis of selenourea, more modern methods concern themselves with synthesis of substituted selenoureas. These can be synthesized using organic isoselenocyanates and secondary amines: :RN=C=Se + NHR′R″ → Se=C(NRH)(NR′R″H) Alternatively, a substituted carbodiimide could be used as follows: :RN=C=NR′ Se=C(NRH)(NR′H) Prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiourea
Thiourea () is an organosulfur compound with the formula and the structure . It is structurally similar to urea (), except that the oxygen atom is replaced by a sulfur atom (as implied by the '' thio-'' prefix); however, the properties of urea and thiourea differ significantly. Thiourea is a reagent in organic synthesis. " Thioureas" refer to a broad class of compounds with the general structure . Thioureas are related to thioamides, e.g. , where R is methyl, ethyl, etc. Structure and bonding Thiourea is a planar molecule. The C=S bond distance is 1.71 Å. The C-N distances average 1.33 Å. The weakening of the C-S bond by C-N pi-bonding is indicated by the short C=S bond in thiobenzophenone, which is 1.63 Å. Thiourea occurs in two tautomeric forms, of which the thione form predominates in aqueous solutions. The equilibrium constant has been calculated as ''K''eq is . The thiol form, which is also known as an isothiourea, can be encountered in substituted compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
Tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is best described as the "average" of the idealized, hypo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbodiimide
In organic chemistry, a carbodiimide (systematic IUPAC name: methanediimine) is a functional group with the formula RN=C=NR. They are exclusively synthetic. A well known carbodiimide is dicyclohexylcarbodiimide, which is used in peptide synthesis. Dialkylcarbodiimides are stable. Some diaryl derivatives tend to convert to dimers and polymers upon standing at room temperature, though this mostly occurs with low melting point carbodiimides that are liquids at room temperature. Solid diaryl carbodiimides are more stable, but can slowly undergo hydrolysis in the presence of water over time. Structure and bonding From the perspective of bonding, carbodiimides are isoelectronic with carbon dioxide. Three principal resonance structures describe carbodiimides: :RN=C=NR ↔ RN+≡C-N−R ↔ RN−-C≡N+R The N=C=N core is relatively linear and the C-N=C angles approach 120°. In the case of C(NCHPh2)2, the central N=C=N angle is 170° and the C-N=C angles are within 1° of 126°. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino
In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; Inorganic derivatives of ammonia are also called amines, such as monochloramine (). The substituent is called an amino group. Compounds with a nitrogen atom attached to a carbonyl group, thus having the structure , are called amides and have different chemical properties from amines. Classification of amines Amines can be classified according to the nature and number of substituents on nitrogen. Aliphatic amines contain only H and alkyl substitue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
