Dimethylformamide

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Dimethylformamide
Identifiers
CAS number68-12-2 YesY
PubChem6228
ChemSpider5993 YesY
UNII8696NH0Y2X YesY
EC number200-679-5
UN number2265
DrugBankDB01844
KEGGC03134 YesY
MeSHDimethylformamide
ChEBICHEBI:17741 YesY
ChEMBLCHEMBL268291 YesY
RTECS numberLQ2100000
Beilstein Reference605365
3DMetB00545
Jmol-3D imagesImage 1
Image 2
Properties
Molecular formulaC3H7NO
Molar mass73.09 g mol−1
AppearanceColourless liquid
Odorfishy, ammoniacal
Density0.948 g mL−1
Melting point

-60 °C, 212.7 K, -77 °F

Boiling point

152-154 °C, 425-427 K, 305-309 °F

Solubility in waterMiscible
log P−0.829
Vapor pressure516 Pa
λmax270 nm
Absorbance1.00
Refractive index (nD)1.4305 (at 20 °C)
Viscosity0.92 mPa s (at 20 °C)
Structure
Dipole moment3.86 D
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−240.6–−238.2 kJ mol−1
Std enthalpy of
combustion
ΔcHo298
−1.9428–−1.9404 MJ mol−1
Specific heat capacity, C146.05 J K−1 mol−1
Hazards
GHS pictogramsThe 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 wordDANGER
GHS hazard statementsH226, H312, H319, H332, H360
GHS precautionary statementsP280, P305+351+338, P308+313
EU Index616-001-00-X
EU classificationToxic T
R-phrasesR61, R20/21, R36
S-phrasesS45
NFPA 704
NFPA 704.svg
2
2
0
Flash point58 °C
Autoignition
temperature
445 °C
Explosive limits2.2–15.2%
Threshold Limit Value30 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
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references
 
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Dimethylformamide
Identifiers
CAS number68-12-2 YesY
PubChem6228
ChemSpider5993 YesY
UNII8696NH0Y2X YesY
EC number200-679-5
UN number2265
DrugBankDB01844
KEGGC03134 YesY
MeSHDimethylformamide
ChEBICHEBI:17741 YesY
ChEMBLCHEMBL268291 YesY
RTECS numberLQ2100000
Beilstein Reference605365
3DMetB00545
Jmol-3D imagesImage 1
Image 2
Properties
Molecular formulaC3H7NO
Molar mass73.09 g mol−1
AppearanceColourless liquid
Odorfishy, ammoniacal
Density0.948 g mL−1
Melting point

-60 °C, 212.7 K, -77 °F

Boiling point

152-154 °C, 425-427 K, 305-309 °F

Solubility in waterMiscible
log P−0.829
Vapor pressure516 Pa
λmax270 nm
Absorbance1.00
Refractive index (nD)1.4305 (at 20 °C)
Viscosity0.92 mPa s (at 20 °C)
Structure
Dipole moment3.86 D
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−240.6–−238.2 kJ mol−1
Std enthalpy of
combustion
ΔcHo298
−1.9428–−1.9404 MJ mol−1
Specific heat capacity, C146.05 J K−1 mol−1
Hazards
GHS pictogramsThe 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 wordDANGER
GHS hazard statementsH226, H312, H319, H332, H360
GHS precautionary statementsP280, P305+351+338, P308+313
EU Index616-001-00-X
EU classificationToxic T
R-phrasesR61, R20/21, R36
S-phrasesS45
NFPA 704
NFPA 704.svg
2
2
0
Flash point58 °C
Autoignition
temperature
445 °C
Explosive limits2.2–15.2%
Threshold Limit Value30 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
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Dimethylformamide is an organic compound with the formula (CH3)2NC(O)H. Commonly abbreviated as DMF (though 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. Pure dimethylformamide is odorless whereas technical grade or degraded dimethylformamide often has a fishy smell due to impurity of dimethylamine. Its name is derived from the fact that 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.[2] Dimethylformamide is not stable in the presence of strong bases like 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.

Contents

Structure and properties

Due to the contribution of the two possible resonance structures of an amide, the bond order of the carbonyl C=O bond is reduced, while 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[3] 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,[3] instead of one singlet of 6 protons in the proton NMR spectrum.

DMF is miscible with water in all proportions.[4] The vapour pressure at 20°C is 3.5hPa.[5] 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.[6] The partition coefficient logPOW is measured to −0.85.[7] Since the density of DMF (0.95 g/cm3 at 20 °C[4]) 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

Dimethyl formamide is produced either via catalyzed reaction of dimethylamine and carbon monoxide in methanol or via the reaction of methyl formate with dimethylamine.[2] It may also be prepared on a laboratory scale by reacting dimethylamine with formic acid.[citation needed]

Applications

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.[8]

Safety

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.[11]

Toxicity

DMF has been linked to cancer in humans, and it is thought to cause birth defects.[12] 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 EPA does not consider it a cancer risk.

References

  1. ^ "Dimethylformamide - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. September 2004. Identification. http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6228&loc=ec_rcs#x291. Retrieved 2012-06-28. 
  2. ^ 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. 
  3. ^ a b "Dimethylformamide". Spectral Database for Organic Compounds. Japan: AIST. http://www.aist.go.jp/RIODB/SDBS/cgi-bin/cre_frame_disp.cgi?sdbsno=324. Retrieved 2012-06-28. 
  4. ^ a b Bipp, H.; Kieczka, H. (2005), "Formamides", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a12_001.pub2 
  5. ^ IPCS (International Programme on Chemical Safety) (1991). Environmental Health Criteria 114 “Dimethylformamide” United Nations Environment Programme, International Labour Organisation, World Health Organization; 1–124.
  6. ^ 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. 
  7. ^ (BASF AG, department of analytical, unpublished data, J-No. 124659/08, 27.11.1987)
  8. ^ 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. PMID 3358569. 
  9. ^ Clayden, J. (2001). Organic Chemistry. Oxford: Oxford University Press. pp. 276–296. ISBN 0-19-850346-6. 
  10. ^ Haddon, R.; Itkis, M. (March 2008). "3. Near-Infrared (NIR) Spectroscopy". In Freiman, S.; Hooker, S.; Migler; K.; Arepalli, S. (pdf). Publication 960-19 Measurement Issues in Single Wall Carbon Nanotubes. NIST. p. 20. http://www.nist.gov/customcf/get_pdf.cfm?pub_id=852726. Retrieved 2012-06-28. 
  11. ^ UK Chemical Reaction Hazards Forum and references cited therein
  12. ^ Hazardous substance fact sheet for Dimethylformamide

External links