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Methylamine is also controlled as a [[DEA_list_of_chemicals|List 1]] [[Precursor (chemistry)|precursor]] chemical by the United States Drug Enforcement Administration (DEA); the [[Drug Enforcement Administration|DEA]] lists methylamine as a precursor (to [[methamphetamine]]).
Methylamine is also controlled as a [[DEA_list_of_chemicals|List 1]] [[Precursor (chemistry)|precursor]] chemical by the United States Drug Enforcement Administration (DEA); the [[Drug Enforcement Administration|DEA]] lists methylamine as a precursor (to [[methamphetamine]]).

==In Popular Culture==
Methylamine is mentioned frequently as an important ingredient in methamphetamine in the television show [[Breaking Bad]].


==References==
==References==

Revision as of 12:58, 6 August 2012

Methylamine
Skeletal formula of methylamine with all explicit hydrogens added
Ball and stick model of methylamine
Ball and stick model of methylamine
Spacefill model of methylamine
Spacefill model of methylamine
Names
Preferred IUPAC name
Aminomethane[citation needed]
Systematic IUPAC name
Methanamine[1]
Other names
Identifiers
3D model (JSmol)
Abbreviations MMA[citation needed]
741851
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.000.746 Edit this at Wikidata
EC Number
  • 200-820-0
145
KEGG
MeSH methylamine
RTECS number
  • PF6300000
UN number 1061
  • InChI=1S/CH5N/c1-2/h2H2,1H3 checkY
    Key: BAVYZALUXZFZLV-UHFFFAOYSA-N checkY
  • CN
Properties
CH5N
Molar mass 31.058 g·mol−1
Appearance Colorless gas
Odor Icthyal, ammoniacal
Melting point −93.10 °C; −135.58 °F; 180.05 K
1.08 kg L−1 (at 20 °C)
log P −0.472
Vapor pressure 186.10 kPa (at 20 °C)
1.4 mmol Pa−1 kg−1
Viscosity 230 μPa s (at 0 °C)
1.31 D
Thermochemistry
−23.5 kJ mol−1
Hazards
GHS labelling:
GHS02: Flammable GHS05: Corrosive GHS07: Exclamation mark
Danger
H220, H315, H318, H332, H335
P210, P261, P280, P305+P351+P338, P410+P403
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g. propaneInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
4
0
Flash point <−30 °C
Explosive limits 4.9–20.8%
Lethal dose or concentration (LD, LC):
100 mg kg−1 (oral, rat)
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Methylamine is the organic compound with a formula of CH3NH2. This colourless gas is a derivative of ammonia, but with one H atom replaced by a methyl group. It is the simplest primary amine. It is sold as a solution in methanol, ethanol, THF, and water, or as the anhydrous gas in pressurized metal containers. Industrially methylamine is sold in its anhydrous form in pressurized railcars and tank trailers. It has a strong odor similar to fish. Methylamine is used as a building block for the synthesis of many other commercially available compounds. Over 1 million tonnes are produced annually.[2]

Production

Methylamine is prepared commercially by the reaction of ammonia with methanol in the presence of a silicoaluminate catalyst. Dimethylamine and trimethylamine are coproduced; the reaction kinetics and reactant ratios determine the ratio of the three products.[3]

CH3OH + NH3 → CH3NH2 + H2O

In this way, more than 400M kg are produced annually.

In the laboratory, methylamine hydrochloride is readily prepared by treating formaldehyde with ammonium chloride.[4]

NH4Cl + H2CO → [CH2=NH2]Cl + H2O
[CH2=NH2]Cl + H2CO + H2O → [CH3NH3]Cl + HCOOH

The colourless hydrochloride salt can be converted to the amine by the addition of strong base, like NaOH:

[CH3NH3]Cl + NaOH → CH3NH2 + NaCl + H2O

Methylamine was first prepared by Wurtz by the hydrolysis of methyl isocyanate and related compounds.[5]

Reactivity and applications

Methylamine is a good nucleophile as it is highly basic and unhindered, although, 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.

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.[5]

Liquid methylamine can be used as a solvent analogous to liquid ammonia. It shares some of the properties of liquid ammonia, but is better for dissolving organic substances, in the same way that methanol is better than water.[6] Methylamine can also be used for scavenging H2S from hydrocarbon in refining applications.

Biological chemistry

Methylamine arises naturally as the result of putrefaction and is a substrate for methanogenesis.[7] It serves as a buffering agent in the lumen of the chloroplast in plants, effectively siphoning off protons that are heading for ATP synthase.[citation needed]

Safety

The LD50 (mouse, s.c.) is 2.5 g/kg.[8]

Methylamine is also controlled as a List 1 precursor chemical by the United States Drug Enforcement Administration (DEA); the DEA lists methylamine as a precursor (to methamphetamine).

Methylamine is mentioned frequently as an important ingredient in methamphetamine in the television show Breaking Bad.

References

  1. ^ "methylamine - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification and Related Records. Retrieved 2 May 2012.
  2. ^ S.N. Bizzari (November 2008). "CEH Marketing Research Report: ALKYLAMINES (C1-C6)". Chemical Economics Handbook. SRI consulting. Retrieved July 2011. {{cite web}}: Check date values in: |accessdate= (help)
  3. ^ Corbin D.R.; Schwarz S.; Sonnichsen G.C. (1997). "Methylamines synthesis: A review". Catalysis Today. 37 (2): 71–102. doi:10.1016/S0920-5861(97)00003-5.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ Marvel, C. S.; Jenkins, R. L. (1941). "Methylamine Hydrochloride". Organic Syntheses{{cite journal}}: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 1, p. 347.
  5. ^ a b Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005.
  6. ^ H. D. Gibbs (1906). "Liquid methylamine as a solvent, and a study of its chemical reactivity". J. Am. Chem. Soc. 28 (10): 1395–1422. doi:10.1021/ja01976a009.
  7. ^ Thauer, R. K., "Biochemistry of Methanogenesis: a Tribute to Marjory Stephenson", Microbiology, 1998, 144, 2377-2406.
  8. ^ The Merck Index, 10th Ed. (1983), p.864, Rahway: Merck & Co.
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