Dimethylamine

Names
Preferred IUPAC name

N-Methylmethanamine

Other names

(Dimethyl)amine

Identifiers

CAS Number

* 124-40-3 Y

3D model (JSmol)

* Interactive image

3DMet  |

* B00125

Beilstein Reference

| 605257
ChEBI |

* CHEBI:17170 Y

ChEMBL |

* ChEMBL120433 Y

ChemSpider |

* 654 Y

EC Number |

* 204-697-4

Gmelin Reference

| 849
KEGG |

* C00543 Y

MeSH | dimethylamine

PubChem CID

* 674

RTECS number |

* IP8750000

UNII |

* ARQ8157E0Q Y

UN number | 1032

InChI

* InChI=1S/C2H7N/c1-3-2/h3H,1-2H3 Y

Key: ROSDSFDQCJNGOL-UHFFFAOYSA-N Y

SMILES

* CNC

Properties[1][2]

Chemical formula

| (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

Solubility in water

| 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
formation (ΔfH⦵298)

| −21 to −17 kJ mol−1
Hazards
GHS pictograms |
GHS Signal word | DANGER

GHS hazard statements

| H220, H302, H315, H318, H332, H335

GHS precautionary statements

| P210, P261, P280, P305+351+338
NFPA 704 (fire diamond)  |

Flash point |  −6 °C (21 °F; 267 K) (liquid)

Autoignition
temperature

|  401 °C (754 °F; 674 K)
Explosive limits | 2.8–14.4%
Lethal dose or concentration (LD, LC):

LD50 (median dose)

| 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)

| 4700 ppm (rat, 4 hr)
4540 ppm (rat, 6 hr)
7650 ppm (mouse, 2 hr)[4]
NIOSH (US health exposure limits):

PEL (Permissible)

| TWA 10 ppm (18 mg/m3)[3]

REL (Recommended)

| TWA 10 ppm (18 mg/m3)[3]

IDLH (Immediate danger)

| 500 ppm[3]
Related compounds

Related amines

* Trimethylamine
* Diethylamine
* Triethylamine
* Diisopropylamine
* Dimethylaminopropylamine
* Triisopropylamine

Related compounds

* Unsymmetrical dimethylhydrazine

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Y verify (what is YN ?)
Infobox references

Tracking categories (test):

* SizeSet

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.[5]

## Contents

* 1 Structure and synthesis
* 2 Natural occurrence
* 3 Uses
* 4 Reactions
* 5 Safety
* 6 See also
* 7 References
* 8 External links

## Structure and synthesis

The molecule consists of a nitrogen atom with two methyl substituents and one hydrogen. Dimethylamine is a weak base and the pKa of the ammonium CH3-NH+2-CH3 is 10.73, a value above methylamine (10.64) and trimethylamine (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 catalytic reaction of methanol and ammonia at elevated temperatures and high pressure:[6]

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.[5][8] It reacts with carbon disulfide to give dimethyl dithiocarbamate, a precursor to zinc bis(dimethyldithiocarbamate) and other chemicals used in the sulfur vulcanization of rubber. Dimethylaminoethoxyethanol is manufactured by reacting dimethylamine and ethylene oxide.[9] Other methods are also available producing streams rich in the substance which then need to be further purified.[10] The solvents dimethylformamide and dimethylacetamide are derived from dimethylamine. It is raw material for the production of many agrichemicals and pharmaceuticals, such as dimefox and diphenhydramine, respectively. The chemical weapon tabun is derived from dimethylamine. The surfactant lauryl dimethylamine oxide is found in soaps and cleaning compounds. Unsymmetrical dimethylhydrazine, a rocket fuel, is prepared from dimethylamine.[11]

(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 organolithium compounds. The resulting LiNMe2, which adopts a cluster-like structure, serves as a source of "Me2N−". This lithium amide has been used to prepare volatile metal complexes such as tetrakis(dimethylamido)titanium and pentakis(dimethylamido)tantalum.

It is also a Lewis base.[13][14]

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 nitrosation to give dimethylnitrosamine, a carcinogen.

## See also

* Methylamine
* Trimethylamine

## References

1. ↑ "Dimethylamine". NIST Chemistry WebBook. USA: National Institute of Standards and Technology. http://webbook.nist.gov/cgi/cbook.cgi?ID=C124403&Mask=1#Thermo-Gas.
2. ↑ "Dimethylamine 38931 - ≥99.0%". Aldrich. Sigma-Aldrich Co.. https://www.sigmaaldrich.com/US/en/product/aldrich/38931.
3. ↑ 3.0 3.1 3.2 NIOSH Pocket Guide to Chemical Hazards. "#0219". National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/npg/npgd0219.html.
4. ↑ 4.0 4.1 "Dimethylamine". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/idlh/124403.html.
5. ↑ 5.0 5.1 Van Gysel, August B.; Musin, Willy (2000). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_535.
6. ↑ 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.
7. ↑ Neurath, G. B. (1977). "Primary and secondary amines in the human environment". Food and Cosmetics Toxicology 15 (4): 275–282. doi:10.1016/s0015-6264(77)80197-1. PMID 590888.
8. ↑ Ashford's Dictionary of Industrial Chemicals, 3rd edition, 2011, pages 3284-3286
9. ↑ Frank, H., 2007. Preparation of N, N-Dimethylaminoethoxyethanol by Reacting Reacting Di-methylamine with Ethylene Oxide US Patent
10. ↑ US8907084B2 - Process for the preparation of 2-(2-aminoethoxy) ethanol (2AEE) and morpholine with 2AEE: morpholine >3 - Google Patents
11. ↑ Schirmann, Jean-Pierre; Bourdauducq, Paul (2001). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a13_177.
12. ↑ The Merck Index, 10th Ed. (1983), p.470, Rahway: Merck & Co.
13. ↑ Laurence, C. and Gal, J-F. Lewis Basicity and Affinity Scales, Data and Measurement, (Wiley 2010) pp 50-51 ISBN 978-0-470-74957-9
14. ↑ Cramer, R. E.; Bopp, T. T. (1977). "Graphical display of the enthalpies of adduct formation for Lewis acids and bases". Journal of Chemical Education 54: 612–613. doi:10.1021/ed054p612. The plots shown in this paper used older parameters. Improved E&C parameters are listed in ECW model.
15. ↑ Gaudry, Michel; Jasor, Yves; Khac, Trung Bui (1979). "Regioselective Mannich Condensation with Dimethyl(Methylene)ammonium Trifluoroacetate: 1-(Dimethylamino)-4-methyl-3-pentanone". Org. Synth. 59: 153. doi:10.15227/orgsyn.059.0153.
16. ↑ 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). https://www.cdc.gov/niosh/npg/npgd0219.html.
* Properties from Air Liquide
* MSDS at airliquide.com

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/Dimethylamine. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Chemistry:Dimethylamine&oldid=246776"
*[CID]: Compound ID
*[H220]: Extremely flammable gas
*[H302]: Harmful if swallowed
*[H315]: Causes skin irritation
*[H318]: Causes serious eye damage
*[H332]: Harmful if inhaled
*[H335]: May cause respiratory irritation
*[P210]: Keep away from heat/sparks/open flames/hot surfaces – No smoking
*[P261]: Avoid breathing dust/fume/gas/mist/vapours/spray
*[P280]: Wear protective gloves/protective clothing/eye protection/face protection
*[P305+351+338]: IF IN EYES: Rinse continuously with water for several minutes. Remove contact lenses if present and easy to do – continue rinsing