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Names | |||
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Pronunciation | /ˌmɛθələˈmiːn/ (METH-ə-lə-MEEN), /ˌmɛθəˈlæmən/ (METH-ə-LA-mən), /məˈθɪləˌmiːn/ (mə-THIL-ə-meen) [1] | ||
Preferred IUPAC name Methanamine [2] | |||
Other names
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Identifiers | |||
3D model (JSmol) | |||
3DMet | |||
Abbreviations | MMA | ||
741851 | |||
ChEBI | |||
ChEMBL | |||
ChemSpider | |||
DrugBank | |||
ECHA InfoCard | 100.000.746 | ||
EC Number |
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145 | |||
KEGG | |||
MeSH | methylamine | ||
PubChem CID | |||
RTECS number |
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UNII | |||
UN number | 1061 | ||
CompTox Dashboard (EPA) | |||
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Properties | |||
CH3NH2 | |||
Molar mass | 31.058 g·mol−1 | ||
Appearance | Colorless gas | ||
Odor | Fishy, ammoniacal | ||
Density | 0.6562 g/cm3 (at 25 °C) | ||
Melting point | −93.10 °C; −135.58 °F; 180.05 K | ||
Boiling point | −6.6 to −6.0 °C; 20.0 to 21.1 °F; 266.5 to 267.1 K | ||
1008 g/L (at 20 °C) | |||
log P | −0.472 | ||
Vapor pressure | 186.10 kPa (at 20 °C) | ||
Henry's law constant (kH) | 1.4 mmol/(Pa·kg) | ||
Acidity (pKa) | 10.66 | ||
Conjugate acid | [CH3NH3]+ (Methylammonium) | ||
-27.0·10−6 cm3/mol | |||
Viscosity | 230 μPa·s (at 0 °C) | ||
1.31 D | |||
Thermochemistry | |||
Std enthalpy of formation (ΔfH⦵298) | −23.5 kJ/mol | ||
Hazards | |||
GHS labelling: | |||
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Danger | |||
H220, H315, H318, H332, H335 | |||
P210, P261, P280, P305+P351+P338, P410+P403 | |||
NFPA 704 (fire diamond) | |||
Flash point | −10 °C; 14 °F; 263 K (liquid, gas is extremely flammable) [3] | ||
430 °C (806 °F; 703 K) | |||
Explosive limits | 4.9–20.7% | ||
Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 100 mg/kg (oral, rat) | ||
LC50 (median concentration) | 1860 ppm (mouse, 2 hr) [3] | ||
NIOSH (US health exposure limits): | |||
PEL (Permissible) | TWA 10 ppm (12 mg/m3) [3] | ||
REL (Recommended) | TWA 10 ppm (12 mg/m3) [3] | ||
IDLH (Immediate danger) | 100 ppm [3] | ||
Safety data sheet (SDS) | emdchemicals.com | ||
Related compounds | |||
Related alkanamines | ethylamine, dimethylamine, trimethylamine | ||
Related compounds | ammonia | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Methylamine is an organic compound with a formula of CH3NH2. This colorless gas is a derivative of ammonia, but with one hydrogen atom being replaced by a methyl group. It is the simplest primary amine.
Methylamine is sold as a solution in methanol, ethanol, tetrahydrofuran, or water, or as the anhydrous gas in pressurized metal containers. Industrially, methylamine is transported in its anhydrous form in pressurized railcars and tank trailers. It has a strong odor similar to rotten fish. Methylamine is used as a building block for the synthesis of numerous other commercially available compounds.
Methylamine has been produced industrially since the 1920s (originally by Commercial Solvents Corporation for dehairing of animal skins). [4] This was made possible by Kazimierz Smoleński and his wife Eugenia who discovered amination of alcohols, including methanol, on alumina or kaolin catalyst after WWI, filed two patent applications in 1919 [5] and published an article in 1921. [4] [6]
It is now prepared commercially by the reaction of ammonia with methanol in the presence of an aluminosilicate catalyst. Dimethylamine and trimethylamine are co-produced; the reaction kinetics and reactant ratios determine the ratio of the three products. The product most favored by the reaction kinetics is trimethylamine. [4]
In this way, an estimated 115,000 tons were produced in 2005. [7]
Methylamine was first prepared in 1849 by Charles-Adolphe Wurtz via the hydrolysis of methyl isocyanate and related compounds. [7] [8] An example of this process includes the use of the Hofmann rearrangement, to yield methylamine from acetamide and bromine. [9] [10]
In the laboratory, methylamine hydrochloride is readily prepared by various other methods. One method entails treating formaldehyde with ammonium chloride. [11]
The colorless hydrochloride salt can be converted to an amine by the addition of a strong base, such as sodium hydroxide (NaOH):
Another method entails reducing nitromethane with zinc and hydrochloric acid. [12]
Another method of methylamine production is spontaneous decarboxylation of glycine with a strong base in water. [13]
Methylamine is a good nucleophile as it is an unhindered amine. [14] As an amine it is considered a weak base. Its use in organic chemistry is pervasive. Some reactions involving simple reagents include: with phosgene to methyl isocyanate, with carbon disulfide and sodium hydroxide to the sodium methyldithiocarbamate, with chloroform and base to methyl isocyanide and with ethylene oxide to methylethanolamines. Liquid methylamine has solvent properties analogous to those of liquid ammonia. [15]
Representative commercially significant chemicals produced from methylamine include the pharmaceuticals ephedrine and theophylline, the pesticides carbofuran, carbaryl, and metham sodium, and the solvents N-methylformamide and N-methylpyrrolidone. The preparation of some surfactants and photographic developers require methylamine as a building block. [7]
Methylamine arises as a result of putrefaction and is a substrate for methanogenesis. [16]
Additionally, methylamine is produced during PADI4-dependent arginine demethylation. [17]
The LD50 (mouse, s.c.) is 2.5 g/kg. [18]
The Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) have set occupational exposure limits at 10 ppm or 12 mg/m3 over an eight-hour time-weighted average. [19]
In the United States, methylamine is controlled as a List 1 precursor chemical by the Drug Enforcement Administration [20] due to its use in the illicit production of methamphetamine. [21]
Fictional characters Walter White and Jesse Pinkman use aqueous methylamine as part of a process to synthesize methamphetamine in the AMC series Breaking Bad . [22] [23]
In chemistry, amines are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Formally, amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines, trimethylamine, and aniline. Inorganic derivatives of ammonia are also called amines, such as monochloramine.
In organic chemistry, isocyanate is the functional group with the formula R−N=C=O. Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyanates are manufactured for the production of polyurethanes, a class of polymers.
Hydrazine is an inorganic compound with the chemical formula N2H4. 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.
Methyl isocyanate (MIC) is an organic compound with the molecular formula CH3NCO. Synonyms are isocyanatomethane and methyl carbylamine. Methyl isocyanate is an intermediate chemical in the production of carbamate pesticides (such as carbaryl, carbofuran, methomyl, and aldicarb). It has also been used in the production of rubbers and adhesives. As an extremely toxic and irritating compound, it is very hazardous to human health. MIC was the principal toxicant involved in the Bhopal gas disaster, which short-term killed 4,000–8,000 people and caused permanent injury and premature deaths to tens of thousands more. It is also a very potent lachrymatory agent.
Chloromethane, also called methyl chloride, Refrigerant-40, R-40 or HCC 40, is an organic compound with the chemical formula CH3Cl. One of the haloalkanes, it is a colorless, sweet-smelling, flammable gas. Methyl chloride is a crucial reagent in industrial chemistry, although it is rarely present in consumer products, and was formerly utilized as a refrigerant. Most chloromethane is biogenic.
Ethylene oxide is an organic compound with the formula C2H4O. It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of a silver catalyst.
Methyl acetate, also known as MeOAc, acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish removers. Methyl acetate is occasionally used as a solvent, being weakly polar and lipophilic, but its close relative ethyl acetate is a more common solvent being less toxic and less soluble in water. Methyl acetate has a solubility of 25% in water at room temperature. At elevated temperature its solubility in water is much higher. Methyl acetate is not stable in the presence of strong aqueous bases or aqueous acids. Methyl acetate is not considered a VOC in the USA.
Formamide is an amide derived from formic acid. It is a colorless liquid which is miscible with water and has an ammonia-like odor. It is chemical feedstock for the manufacture of sulfa drugs and other pharmaceuticals, herbicides and pesticides, and in the manufacture of hydrocyanic acid. It has been used as a softener for paper and fiber. It is a solvent for many ionic compounds. It has also been used as a solvent for resins and plasticizers. Some astrobiologists suggest that it may be an alternative to water as the main solvent in other forms of life.
The Hofmann rearrangement is the organic reaction of a primary amide to a primary amine with one less carbon atom. The reaction involves oxidation of the nitrogen followed by rearrangement of the carbonyl and nitrogen to give an isocyanate intermediate. The reaction can form a wide range of products, including alkyl and aryl amines.
Trimethylamine (TMA) is an organic compound with the formula N(CH3)3. It is a trimethylated derivative of ammonia. TMA is widely used in industry. At higher concentrations it has an ammonia-like odor, and can cause necrosis of mucous membranes on contact. At lower concentrations, it has a "fishy" odor, the odor associated with rotting fish.
Triethylamine is the chemical compound with the formula N(CH2CH3)3, commonly abbreviated Et3N. It is also abbreviated TEA, yet this abbreviation must be used carefully to avoid confusion with triethanolamine or tetraethylammonium, for which TEA is also a common abbreviation. It is a colourless volatile liquid with a strong fishy odor reminiscent of ammonia. Like diisopropylethylamine (Hünig's base), triethylamine is commonly employed in organic synthesis, usually as a base.
Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA).
Dimethyl sulfate (DMS) is a chemical compound with formula (CH3O)2SO2. As the diester of methanol and sulfuric acid, its formula is often written as (CH3)2SO4 or Me2SO4, where CH3 or Me is methyl. Me2SO4 is mainly used as a methylating agent in organic synthesis. Me2SO4 is a colourless oily liquid with a slight onion-like odour. Like all strong alkylating agents, Me2SO4 is toxic. Its use as a laboratory reagent has been superseded to some extent by methyl triflate, CF3SO3CH3, the methyl ester of trifluoromethanesulfonic acid.
Dimethylacetamide (DMAc or DMA) is the organic compound with the formula CH3C(O)N(CH3)2. This colorless, water-miscible, high-boiling liquid is commonly used as a polar solvent in organic synthesis. DMA is miscible with most other solvents, although it is poorly soluble in aliphatic hydrocarbons.
Dimethylamine is an organic compound with the formula (CH3)2NH. This secondary amine is a colorless, flammable gas with an ammonia-like odor. Dimethylamine is commonly encountered commercially as a solution in water at concentrations up to around 40%. An estimated 270,000 tons were produced in 2005.
Ethylamine, also known as ethanamine, is an organic compound with the formula CH3CH2NH2. This colourless gas has a strong ammonia-like odor. It condenses just below room temperature to a liquid miscible with virtually all solvents. It is a nucleophilic base, as is typical for amines. Ethylamine is widely used in chemical industry and organic synthesis.
Diethylamine is an organic compound with the formula (CH3CH2)2NH. It is a secondary amine. It is a flammable, weakly alkaline liquid that is miscible with most solvents. It is a colorless liquid, but commercial samples often appear brown due to impurities. It has a strong ammonia-like odor.
n-Butylamine is an organic compound (specifically, an amine) with the formula CH3(CH2)3NH2. This colourless liquid is one of the four isomeric amines of butane, the others being sec-butylamine, tert-butylamine, and isobutylamine. It is a liquid having the fishy, ammonia-like odor common to amines. The liquid acquires a yellow color upon storage in air. It is soluble in all organic solvents. Its vapours are heavier than air and it produces toxic oxides of nitrogen during combustion.
1-Methylimidazole or N-methylimidazole is an aromatic heterocyclic organic compound with the formula CH3C3H3N2. It is a colourless liquid that is used as a specialty solvent, a base, and as a precursor to some ionic liquids. It is a fundamental nitrogen heterocycle and as such mimics for various nucleoside bases as well as histidine and histamine.
Methoxyamine is the organic compound with the formula CH3ONH2. Also called O-methylhydroxylamine, it is a colourless volatile liquid that is soluble in polar organic solvent and in water. It is a derivative of hydroxylamine with the hydroxyl hydrogen replaced by a methyl group. Alternatively, it can be viewed as a derivative of methanol with the hydroxyl hydrogen replaced by an amino group. It is an isomer of N-methylhydroxylamine and aminomethanol. It decomposes in an exothermic reaction (-56 kJ/mol) to methane and azanone unless stored as a hydrochloride salt.
...an unhindered amine such as methylamine