Dimethylformamide

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Dimethylformamide
Skeletal formula of dimethylformamide with one explicit hydrogen added
Ball and stick model of dimethylformamide Spacefill model of dimethylformamide
Identifiers
CAS number 68-12-2 YesY
PubChem 6228
ChemSpider 5993 YesY
UNII 8696NH0Y2X YesY
EC number 200-679-5
UN number 2265
DrugBank DB01844
KEGG C03134 YesY
MeSH Dimethylformamide
ChEBI CHEBI:17741 YesY
ChEMBL CHEMBL268291 YesY
RTECS number LQ2100000
Beilstein Reference 605365
3DMet B00545
Jmol-3D images Image 1
Image 2
Properties
Molecular formula C3H7NO
Molar mass 73.09 g mol−1
Appearance Colourless liquid
Odor fishy, ammoniacal
Density 0.948 g mL−1
Melting point −60.5 °C; −76.8 °F; 212.7 K
Boiling point 152 to 154 °C; 305 to 309 °F; 425 to 427 K
Solubility in water Miscible
log P −0.829
Vapor pressure 516 Pa
λmax 270 nm
Absorbance 1.00
Refractive index (nD) 1.4305 (at 20 °C)
Viscosity 0.92 mPa s (at 20 °C)
Structure
Dipole moment 3.86 D
Thermochemistry
Specific
heat capacity
C
146.05 J K−1 mol−1
Std enthalpy of
formation
ΔfHo298
−240.6–−238.2 kJ mol−1
Std enthalpy of
combustion
ΔcHo298
−1.9428–−1.9404 MJ mol−1
Hazards
MSDS External MSDS
GHS pictograms The flame pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The health hazard pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
GHS signal word DANGER
GHS hazard statements H226, H312, H319, H332, H360
GHS precautionary statements P280, P305+351+338, P308+313
EU Index 616-001-00-X
EU classification Toxic T
R-phrases R61, R20/21, R36
S-phrases S53, 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
Flash point 58 °C (136 °F; 331 K)
Explosive limits 2.2–15.2%
Threshold Limit Value 30 mg m−3 (TWA)
LD50
  • 1.5 g kg−1 (dermal, rabbit)
  • 2.8 g kg−1 (oral, rat)
Related compounds
Related alkanamides
Related compounds
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Dimethylformamide is an organic compound with the formula (CH3)2NC(O)H. Commonly abbreviated as DMF (although this acronym is sometimes used for dimethylfuran), this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions. Dimethylformamide is odorless whereas technical grade or degraded samples often have a fishy smell due to impurity of dimethylamine. As its name indicates, it is a derivative of formamide, the amide of formic acid.

Dimethylformamide is a polar (hydrophilic) aprotic solvent with a high boiling point. It facilitates reactions that follow polar mechanisms, such as SN2 reactions. Dimethylformamide can be synthesized from methyl formate and dimethylamine or by reaction of dimethylamine with carbon monoxide.[3] Dimethylformamide is reactive toward strong bases such as sodium hydroxide or strong acids such as hydrochloric acid or sulfuric acid and is hydrolyzed back into formic acid and dimethylamine, especially at elevated temperatures.

Structure and properties[edit]

Due to the contribution of the two major resonance structures of an amide, the bond order of the carbonyl C=O bond is reduced and that of the carbon–nitrogen bond is increased. Thus the infrared spectrum of DMF shows a lower C=O stretching frequency at 1675 cm−1[4] than an unsubstituted C=O bond. Also, because of the partial double bond character, the rotation about the C-N axis is slow at room temperature, making the two methyl groups inequivalent on the NMR time scale, giving rise to two singlets of 3 protons each at δ 2.97 and 2.88,[4] instead of one singlet of 6 protons in the proton NMR spectrum.

DMF is miscible with water in all proportions.[5] The vapour pressure at 20°C is 3.5hPa.[6] A Henry's law constant of 7.47×10−5 hPa·m3/mol can be deduced from an experimentally determined equilibrium constant at 25 °C.[7] The partition coefficient logPOW is measured to −0.85.[8] Since the density of DMF (0.95 g/cm3 at 20 °C[5]) is very similar to that of water, significant flotation or stratification in surface waters in case of accidental losses is not expected.

The two resonance forms of DMF

Production[edit]

Dimethyl formamide is produced either via a catalyzed reaction of dimethylamine and carbon monoxide in methanol or via the reaction of methyl formate with dimethylamine.[3]

Applications[edit]

The primary use of dimethylformamide is as a solvent with low evaporation rate. DMF is used in the production of acrylic fibers and plastics. It is also used as a solvent in peptide coupling for pharmaceuticals, in the development and production of pesticides, and in the manufacture of adhesives, synthetic leathers, fibers, films, and surface coatings.[9]


Niche uses[edit]

As a common and cheap reagent, DMF has many uses in the research laboratory.

Safety[edit]

Reactions including the use of sodium hydride in DMF as a solvent are somewhat hazardous; exothermic decompositions have been reported at temperatures as low as 26 °C. On a laboratory scale any thermal runaway is (usually) quickly noticed and brought under control with an ice bath and this remains a popular combination of reagents. On a pilot plant scale, on the other hand, several accidents have been reported.[13]

Toxicity[edit]

DMF has been linked to cancer in humans, and it is thought to cause birth defects.[14] In some sectors of industry, women are banned from working with DMF. For many reactions, it can be replaced with dimethyl sulfoxide. Most manufacturers of DMF list 'Life' or 'Chronic' as a health hazard in their MSDS since DMF is not readily disposed of by the body. According to IARC, DMF is a possible carcinogen, although the United States Environmental Protection Agency does not consider it a cancer risk.[citation needed]

References[edit]

  1. ^ "Dimethylformamide – Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. September 2004. Identification. Retrieved 2012-06-28. 
  2. ^ N,N-Dimethylmethanamide, NIST web thermo tables
  3. ^ a b Weissermel, K.; Arpe, H.-J. Industrial Organic Chemistry: Important Raw Materials and Intermediates. Wiley-VCH. pp. 45–46. ISBN 3-527-30578-5. 
  4. ^ a b "Dimethylformamide". Spectral Database for Organic Compounds. Japan: AIST. Retrieved 2012-06-28. 
  5. ^ a b Bipp, H.; Kieczka, H. (2005), "Formamides", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a12_001.pub2 
  6. ^ IPCS (International Programme on Chemical Safety) (1991). Environmental Health Criteria 114 “Dimethylformamide” United Nations Environment Programme, International Labour Organisation, World Health Organization; 1–124.
  7. ^ Taft, R. W.; Abraham, M. H.; Doherty, R. M.; Kamlet, M. J. (1985). "The molecular properties governing solubilities of organic nonelectrolytes in water". Nature 313 (6001): 384–386. doi:10.1038/313384a0. 
  8. ^ (BASF AG, department of analytical, unpublished data, J-No. 124659/08, 27.11.1987)
  9. ^ Redlich, C.; Beckett, W. S.; Sparer, J.; Barwick, K. W.; Riely, C. A.; Miller, H.; Sigal, S. L.; Shalat, S. L.; Cullen, M. R. (1988). "Liver disease associated with occupational exposure to the solvent dimethylformamide". Annals of Internal Medicine 108 (5): 680–686. doi:10.7326/0003-4819-108-5-680. PMID 3358569. 
  10. ^ Clayden, J. (2001). Organic Chemistry. Oxford: Oxford University Press. pp. 276–296. ISBN 0-19-850346-6. 
  11. ^ Ansell, M. F. in "The Chemistry of Acyl Halides"; S. Patai, Ed.; John Wiley and Sons: London, 1972; pp 35–68.
  12. ^ Haddon, R.; Itkis, M. (March 2008). "3. Near-Infrared (NIR) Spectroscopy". In Freiman, S.; Hooker, S.; Migler; K.; Arepalli, S. Publication 960-19 Measurement Issues in Single Wall Carbon Nanotubes (pdf). NIST. p. 20. Retrieved 2012-06-28. 
  13. ^ UK Chemical Reaction Hazards Forum and references cited therein
  14. ^ Hazardous substance fact sheet for Dimethylformamide

External links[edit]