Dimethylamine
Names | |
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Preferred IUPAC name
N-Methylmethanamine | |
Other names
(Dimethyl)amine
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Identifiers | |
3D model (
JSmol ) |
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3DMet | |
605257 | |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard
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100.004.272 |
EC Number |
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849 | |
KEGG | |
MeSH | dimethylamine |
PubChem CID
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RTECS number
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UNII | |
UN number | 1032 |
CompTox Dashboard (EPA)
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Properties[1][2] | |
(CH3)2NH | |
Molar mass | 45.085 g·mol−1 |
Appearance | Colorless gas |
Odor | Fishy, ammoniacal |
Density | 649.6 kg m−3 (at 25 °C) |
Melting point | −93.00 °C; −135.40 °F; 180.15 K |
Boiling point | 7 to 9 °C; 44 to 48 °F; 280 to 282 K |
1.540 kg L−1 | |
log P | −0.362 |
Vapor pressure | 170.3 kPa (at 20 °C) |
Henry's law
constant (kH) |
310 μmol Pa−1 kg−1 |
Basicity (pKb) | 3.29 |
Thermochemistry | |
Std enthalpy of (ΔfH⦵298)formation |
−21 to −17 kJ mol−1 |
Hazards | |
GHS labelling: | |
Danger | |
H220, H302, H315, H318, H332, H335 | |
P210, P261, P280, P305+P351+P338 | |
NFPA 704 (fire diamond) | |
Flash point | −6 °C (21 °F; 267 K) (liquid) |
401 °C (754 °F; 674 K) | |
Explosive limits
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2.8–14.4% |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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698 mg/kg (rat, oral) 316 mg/kg (mouse, oral) 240 mg/kg (rabbit, oral) 240 mg/kg (guinea pig, oral)[4] |
LC50 (median concentration)
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4700 ppm (rat, 4 hr) 4540 ppm (rat, 6 hr) 7650 ppm (mouse, 2 hr)[4] |
NIOSH (US health exposure limits): | |
PEL (Permissible)
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TWA 10 ppm (18 mg/m3)[3] |
REL (Recommended)
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TWA 10 ppm (18 mg/m3)[3] |
IDLH (Immediate danger) |
500 ppm[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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Dimethylamine is an
Structure and synthesis
The molecule consists of a
(9.79).Dimethylamine reacts with acids to form salts, such as dimethylamine hydrochloride, an odorless white solid with a melting point of 171.5 °C. Dimethylamine is produced by
- 2 CH3OH + NH3 → (CH3)2NH + 2 H2O
Natural occurrence
Dimethylamine is found quite widely distributed in animals and plants, and is present in many foods at the level of a few mg/kg.[7]
Uses
Dimethylamine is a precursor to several industrially significant compounds.
- (CH3)2NH + NH2Cl → (CH3)2NNH2 ⋅ HCl
It is an attractant for boll weevils.[12]
Reactions
It is basic, in both the Lewis and Brønsted senses. It easily forms dimethylammonium salts upon treatment with acids. Deprotonation of dimethylamine can be effected with
It is also a
It reacts with many carbonyl compounds. Aldehydes give aminals. For example reaction of dimethylamine and formaldehyde gives bis(dimethylamino)methane:[15]
- 2 (CH3)2NH + CH2O → [(CH3)2N]2CH2 + H2O
It converts esters to dimethylamides.
Safety
Dimethylamine is not very toxic with the following LD50 values: 736 mg/kg (mouse, i.p.); 316 mg/kg (mouse, p.o.); 698 mg/kg (rat, p.o.); 3900 mg/kg (rat, dermal); 240 mg/kg (guinea pig or rabbit, p.o.).[16]
Although not acutely toxic, dimethylamine undergoes
See also
References
- ^ "Dimethylamine". NIST Chemistry WebBook. USA: National Institute of Standards and Technology. Retrieved 15 February 2022.
- ^ "Dimethylamine 38931 - ≥99.0%". Aldrich. Sigma-Aldrich Co. Retrieved 15 February 2022.
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0219". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b "Dimethylamine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ ISBN 978-3527306732.
- .
- PMID 590888.
- ^ Ashford's Dictionary of Industrial Chemicals, 3rd edition, 2011, pages 3284-3286
- ^ Frank, H., 2007. Preparation of N, N-Dimethylaminoethoxyethanol by Reacting Reacting Di-methylamine with Ethylene Oxide US Patent
- ^ US8907084B2 - Process for the preparation of 2-(2-aminoethoxy) ethanol (2AEE) and morpholine with 2AEE: morpholine >3 - Google Patents
- ISBN 978-3527306732.
- ^ The Merck Index, 10th Ed. (1983), p.470, Rahway: Merck & Co.
- ISBN 978-0-470-74957-9.
- doi:10.1021/ed054p612. The plots shown in this paper used older parameters. Improved E&C parameters are listed in ECW model.
- .
- ^ Chemical Information Profile for Dimethylamine Borane, National Toxicology Program, NIEHS, NIH (2008), p.4: http://ntp.niehs.nih.gov/ntp/htdocs/Chem_Background/ExSumPdf/DimethylamineBorane508.pdf
External links
- International Chemical Safety Card 0260 (gas)
- International Chemical Safety Card 1485 (aqueous solution)
- NIOSH Pocket Guide to Chemical Hazards. "#0219". National Institute for Occupational Safety and Health (NIOSH).
- Properties from Air Liquide
- MSDS at airliquide.com