Trimethylamine
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| Identifiers | |||
|---|---|---|---|
| 75-50-3 | |||
| 3DMet | B00133 | ||
| 956566 | |||
| ChEBI | CHEBI:18139 | ||
| ChEMBL | ChEMBL439723 | ||
| ChemSpider | 1114 | ||
| EC Number | 200-875-0 | ||
| Jmol interactive 3D | Image | ||
| KEGG | C00565 | ||
| PubChem | 1146 | ||
| RTECS number | PA0350000 | ||
| UNII | LHH7G8O305 | ||
| UN number | 1083 | ||
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| Properties | |||
| C3H9N | |||
| Molar mass | 59.11 g·mol−1 | ||
| Appearance | Colorless gas | ||
| Odor | Fishy, ammoniacal | ||
| Density | 670 kg m−3 (at 0 °C) 627.0 kg m−3 (at 25 °C) | ||
| Melting point | −117.20 °C; −178.96 °F; 155.95 K | ||
| Boiling point | 3 to 7 °C; 37 to 44 °F; 276 to 280 K | ||
| Miscible | |||
| log P | 0.119 | ||
| Vapor pressure | 188.7 kPa (at 20 °C) [2] | ||
| Henry's law constant (kH) |
95 μmol Pa−1 kg−1 | ||
| Basicity (pKb) | 4.19 | ||
| Thermochemistry | |||
| Std enthalpy of formation (ΔfH |
−24.5 to −23.0 kJ mol−1 | ||
| Hazards | |||
| GHS pictograms | ![]() | ||
| GHS signal word | DANGER | ||
| H220, H315, H318, H332, H335 | |||
| P210, P261, P280, P305+351+338 | |||
| EU classification (DSD) |
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| R-phrases | R12, R20, R37/38, R41 | ||
| S-phrases | (S2), S16, S26, S29 | ||
| NFPA 704 | |||
| Flash point | −7 °C (19 °F; 266 K) | ||
| 190 °C (374 °F; 463 K) | |||
| Explosive limits | 2–11.6% | ||
| Lethal dose or concentration (LD, LC): | |||
| LD50 (Median dose) |
500 mg kg−1 (oral, rat) | ||
| US health exposure limits (NIOSH): | |||
| PEL (Permissible) |
none[3] | ||
| REL (Recommended) |
TWA 10 ppm (24 mg/m3) ST 15 ppm (36 mg/m3)[3] | ||
| IDLH (Immediate danger |
N.D.[3] | ||
| Related compounds | |||
| Related amines |
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| Related compounds |
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| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |||
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| 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 rotting fish, some infections, bad breath and can be a cause of vaginal odor due to bacterial vaginosis. 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:[4]
- 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,[5] 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 or herbicides, strongly basic anion exchange resins, dye leveling agents and a number of basic dyes.[4][6] Gas sensors to test for fish freshness detect trimethylamine.
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.
See also
- Ammonia, NH3
- Ammonium, NH4+
- Methylamine, (CH3)NH2
- Triethylamine (TEA)
References
- ↑ Merck Index, 11th Edition, 9625.
- ↑ The Vapor Pressure of Trimethylamine from 0 to 40° (http://pubs.acs.org/doi/abs/10.1021/ja01221a508)
- 1 2 3 "NIOSH Pocket Guide to Chemical Hazards #0636". National Institute for Occupational Safety and Health (NIOSH).
- 1 2 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
- ↑ Roger Adams, B. K. Brown. "Trimethylamine". Org. Synth.; Coll. Vol. 1, p. 75
- ↑ 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
- CDC - NIOSH Pocket Guide to Chemical Hazards
| Wikimedia Commons has media related to Trimethylamine. |
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