Dimethylacetamide

Dimethylacetamide
Names
IUPAC name
N,N-Dimethylacetamide[1]
Identifiers
Abbreviations DMAc[2]
1737614
127-19-5 Yes
ChEBI CHEBI:84254 
ChEMBL ChEMBL11873 Yes
ChemSpider 29107 Yes
EC number 204-826-4
Jmol-3D images Image
Image
MeSH dimethylacetamide
PubChem 31374
RTECS number AB7700000
UNII JCV5VDB3HY Yes
Properties
Molecular formula
 C4H9NO
Molar mass 87.12 g·mol−1
Appearance Colorless liquid
Odor Ammoniacal
Density 0.937 g mL−1
Melting point −20 °C (−4 °F; 253 K)
Boiling point 165.1 °C; 329.1 °F; 438.2 K
Miscible
log P −0.253
Vapor pressure 300 Pa
UV-vis (λmax) 270 nm
Absorbance 1.00
1.4375
Viscosity 0.945 mPa s [3]
Thermochemistry
Specific
heat capacity (C)
 178.2 J K−1 mol−1
Std enthalpy of
formation (ΔfHo298)
 −300.1 kJ mol−1
Std enthalpy of
combustion (ΔcHo298)
 −2.5835–−2.5805 MJ mol−1
Hazards
GHS pictograms
GHS signal word DANGER
H312, H332, H360
P280, P308+313
EU Index 616-011-00-4
EU classification T
R-phrases R61, R20/21
S-phrases S45
NFPA 704
Flammability code 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g., diesel fuel Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
2
2
0
Flash point 63 °C (145 °F; 336 K)
490 °C (914 °F; 763 K)
Explosive limits 1.8–11.5%
  • 2.24 g kg−1 (dermal, rabbit)
  • 4.3 g kg−1 (oral, rat)
US health exposure limits (NIOSH):
TWA 10 ppm (35 mg/m3) [skin][4]
TWA 10 ppm (35 mg/m3) [skin][4]
300 ppm[4]
Related compounds
Related compounds
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Dimethylacetamide (DMA) is the organic compound with the formula CH3C(O)N(CH3)2. This colorless, water-miscible, high boiling liquid is commonly used as a polar solvent in organic synthesis. DMA is miscible with most other solvents, although it is poorly soluble in aliphatic hydrocarbons.

Synthesis, reactions, applications

DMA is prepared by the reaction of dimethylamine with acetic anhydride and esters of acetic acid. Dehydration of the salt of dimethylamine and acetic acid also furnishes this compound:[5]

CH3CO2H·HN(CH3)2 → H2O + CH3CON(CH3)2

The chemical reactions of dimethylacetamide are typical of N,N-disubstituted amides. It will hydrolyze in the presence of acids:

CH3CON(CH3)2 + H2O + HCl → CH3COOH + (CH3)2NH2+Cl−

It is however resistant to bases. For this reason DMA is useful solvent for reactions involving strong bases such as sodium hydroxide.[6]

Dimethylacetamide is commonly used as a solvent for fibers (e.g., polyacrylonitrile, spandex) or in the adhesive industry.[5] It is also employed in the production of pharmaceuticals and plasticizers as a reaction medium.

Dimethylacetamide is also used as an excipient in drugs, e.g. in Vulmon (teniposide), Busulfex (busulfan) or Amsidine (amsacrine).

Toxicity

Dimethylacetamide is a medium potency reproductive toxicant (toxic for reproduction, category 1B).[7]

There are indications that dimethylacetamide is incompatible with polycarbonate or ABS. Devices (e.g. syringes) that contain polycarbonate or ABS dissolve when coming into contact with dimethylacetamide.[8]

Regulation

In 2011, dimethylacetamide was identified in the EU as a Substance of very high concern (SVHC).[9] In 2014, the European Commission has started an investigation to restrict the use of dimethylacetamide in the EU according to REACH.[10]

References

  1. ↑ "dimethylacetamide - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 2005-03-26. Identification. Retrieved 2012-04-19.
  2. ↑ Munro, D. D.; Stoughto, R. B. (1965). "Dimethylacetamide (DMAC) and Dimethylformamide (DMFA). Effect on Percutaneous Absorption". Archives of Dermatology 92 (5): 585–586. doi:10.1001/archderm.1965.01600170101020. PMID 5844405.
  3. ↑ Iloukhani, H., and K. Khanlarzadeh. "Densities, viscosities, and refractive indices for binary and ternary mixtures of N, N-dimethylacetamide (1)+ 2-methylbutan-2-ol (2)+ ethyl acetate (3) at 298.15 K for the liquid region and at ambient pressure." Journal of Chemical & Engineering Data 51.4 (2006): 1226-1231. DOI: 10.1021/je050538q
  4. ↑ 4.0 4.1 4.2 "NIOSH Pocket Guide to Chemical Hazards #0218". National Institute for Occupational Safety and Health (NIOSH).
  5. ↑ 5.0 5.1 Cheung, H.; Tanke, R. S.; Torrence, G. P. (2005), "Acetic Acid", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a01_045.pub2
  6. ↑ Zen, S.; Kaji, E. (1977). "Dimethyl nitrosuccinate". Org. Synth. 57: 60.; Coll. Vol. 6, p. 503
  7. ↑ European Chemicals Agency, Opinion on N,N-Dimethylacetamide (DMAC), 12 September 2014
  8. ↑ FDA warns health care professionals not to use Treanda Injection (solution) with closed system transfer devices, adapters, and syringes containing polycarbonate or acrylonitrile-butadiene-styrene – 10 March 2015
  9. ↑ Agreement of the Member State Committee on the Identification of N,N-Dimethylacetamide (DMAC) as a Substance of Very High Concern – Adopted on 24 November 2011
  10. ↑ Official Journal of the European Union, 19.8.2014, Commission Regulation (EU) No 895/2014

External links