Trimethylamine

Trimethylamine[1]
IUPAC name Trimethylamine
Other names N,N-Dimethylmethanamine
Identifiers
Abbreviations	TMA, NMe3
CAS number	75-50-3 Y
PubChem	1146
ChemSpider	1114 Y
UNII	LHH7G8O305 Y
EC number	200-875-0
UN number	1083 (anhydrous) 1297 (solution)
ChEBI	CHEBI:18139 N
ChEMBL	CHEMBL439723 Y
RTECS number	1.1.78 – 31.1.87
Jmol-3D images	Image 1
SMILES N(C)(C)C
InChI InChI=1S/C3H9N/c1-4(2)3/h1-3H3 Y Key: GETQZCLCWQTVFV-UHFFFAOYSA-N Y InChI=1/C3H8N/c1-4(2)3/h1H2,2-3H3 InChI=1/C3H9N/c1-4(2)3/h1-3H3 Key: GETQZCLCWQTVFV-UHFFFAOYAA
Properties
Molecular formula	C3H9N
Molar mass	59.11 g/mol
Appearance	Colorless gas
Density	670 g/L (0 °C)
Melting point	-117.08 °C, 156 K, -179 °F
Boiling point	2.87 °C, 276 K, 37 °F
Solubility in water	Miscible
Acidity (pKa)	9.76[2]
Hazards
R-phrases	R12 R20/22 R34
S-phrases	(S1/2) S3 S16 S26 S29 S36/37/39 S45
NFPA 704	4 2 0
N (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Trimethylamine is an organic compound with the formula N(CH₃)₃. This colorless, hygroscopic, and flammable tertiary amine has a strong "fishy" odor in low concentrations and an ammonia-like odor at higher concentrations. It is a gas at room temperature but is usually sold in pressurized gas cylinders or as a 40% solution in water.

Trimethylamine is a product of decomposition of plants and animals. It is the substance mainly responsible for the odor often associated with fouling fish, some infections, and bad breath. It is also associated with taking large doses of choline and carnitine.

Trimethylamine is a nitrogenous base and can be readily protonated to give trimethylammonium cation. Trimethylammonium chloride is a hygroscopic colorless solid prepared from hydrochloric acid. Trimethylamine is a good nucleophile, and this reaction is the basis of most of its applications.

Production

Trimethylamine is prepared by the reaction of ammonia and methanol employing a catalyst:^[3]

3 CH₃OH + NH₃ → (CH₃)₃N + 3 H₂O

This reaction coproduces the other methylamines, dimethylamine (CH₃)₂NH and methylamine CH₃NH₂.

Trimethylamine has also been prepared via a reaction of ammonium chloride and paraformaldehyde,^[4] according to the following equation:

9 (CH₂=O)_n + 2n NH₄Cl → 2n (CH₃)₃N•HCl + 3n H₂O + 3n CO₂↑

Applications

Trimethylamine is used in the synthesis of choline, tetramethylammonium hydroxide, plant growth regulators, strongly basic anion exchange resins, dye leveling agents and a number of basic dyes.^[3][5] Gas sensors to test for fish freshness detect trimethylamine.

Trimethylaminuria

Main article: Trimethylaminuria

Trimethylaminuria is a genetic disorder in which the body is unable to metabolize trimethylamine from food sources. Patients develop a characteristic fish odour of their sweat, urine, and breath after the consumption of choline-rich foods. Trimethylaminuria is an autosomal recessive disorder involving a trimethylamine oxidase deficiency. A condition similar to trimethylaminuria has also been observed in a certain breed of Rhode Island Red chicken that produces eggs with a fishy smell, especially after eating food containing a high proportion of rapeseed.^{[citation needed]}

See also

• Ammonia, NH₃
• Ammonium, NH₄⁺
• Methylamine (CH₃)NH₂
• Dimethylamine (CH₃)₂NH
• Triethylamine (TEA)

References

1. ^ Merck Index, 11th Edition, 9625.
2. ^ Hall, H.K. (1957). "Correlation of the Base Strengths of Amines". J. Am. Chem. Soc. 79: 5441. doi:10.1021/ja01577a030. 
3. ^ ^{a b} A. B. van Gysel, W. Musin "Methylamines" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. doi:10.1002/14356007.a16 535
4. ^ Roger Adams, B. K. Brown, "Trimethylamine", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV1P0531 ; Coll. Vol. 1: 75 
5. ^ Ashford's Dictionary of Industrial Chemicals (3rd ed.). 2011. p. 9362. ISBN 978-0-9522674-3-0. 

External links

• Molecule of the Month: Trimethylamine
• NIST Webbook data