Dimethylformamide

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Dimethylformamide
Skeletal formula of dimethylformamide with one explicit hydrogen added
Ball and stick model of dimethylformamide
Ball and stick model of dimethylformamide
Spacefill model of dimethylformamide
Spacefill model of dimethylformamide
Names
Preferred IUPAC name
N,N-Dimethylformamide[2]
Other names
Dimethylformamide
N,N-Dimethylmethanamide[1]
DMF
Identifiers
3D model (
JSmol
)
3DMet
605365
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard
 100.000.617 Edit this at Wikidata
EC Number
  • 200-679-5
KEGG
MeSH Dimethylformamide
RTECS number
  • LQ2100000
UNII
UN number 2265
  • InChI=1S/C3H7NO/c1-4(2)3-5/h3H,1-2H3 checkY
    Key: ZMXDDKWLCZADIW-UHFFFAOYSA-N checkY
  • CN(C)C=O
Properties
C3H7NO
Molar mass 73.095 g·mol−1
Appearance Colourless liquid
Odor Odorless, fishy if impure
Density 0.948 g/mL
Melting point −61 °C (−78 °F; 212 K)
Boiling point 153 °C (307 °F; 426 K)
Miscible
log P −0.829
Vapor pressure 516 Pa
Acidity (pKa) −0.3 (for the conjugate acid) (H2O)[3]
UV-vis (λmax) 270 nm
Absorbance 1.00
1.4305 (at 20 °C)
Viscosity 0.92 mPa·s (at 20 °C)
Structure
3.86 D
Thermochemistry
146.05 J/(K·mol)
Std enthalpy of
formation
(ΔfH⦵298)
 −239.4 ± 1.2 kJ/mol
Std enthalpy of
combustion
(ΔcH⦵298)
 −1.9416 ± 0.0012 MJ/mol
Hazards
GHS labelling:
GHS02: Flammable GHS07: Exclamation mark GHS08: Health hazard
Danger
H226, H312, H319, H332, H360
P280, P305+P351+P338, P308+P313
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 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 fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
2
0
Flash point 58 °C (136 °F; 331 K)
445 °C (833 °F; 718 K)
Explosive limits
 2.2–15.2%
30 mg/m3 (TWA)
Lethal dose or concentration (LD, LC):
  • 1.5 g/kg (rabbit, dermal)
  • 2.8 g/kg (rat, oral)
  • 3.7 g/kg (mouse, oral)
  • 3.5 g/kg (rat, oral)
3092 ppm (mouse, 2 h)[5]
5000 ppm (rat, 6 h)[5]
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 10 ppm (30 mg/m3) [skin][4]
REL (Recommended)
 TWA 10 ppm (30 mg/m3) [skin][4]
IDLH
(Immediate danger)
 500 ppm[4]
Related compounds
Related alkanamides
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Dimethylformamide is an

SN2
reactions.

Structure and properties

As for most amides, the spectroscopic evidence indicates partial double bond character for the C−N and C−O bonds. Thus, the infrared spectrum shows a C=O stretching frequency at only 1675 cm−1, whereas a ketone would absorb near 1700 cm−1.[6]

DMF is a classic example of a fluxional molecule.[7]

The ambient temperature 1H NMR spectrum shows two methyl signals, indicative of hindered rotation about the (O)C−N bond.[6] At temperatures near 100 °C, the 500 MHz NMR spectrum of this compound shows only one signal for the methyl groups.

DMF is miscible with water.[8] The vapour pressure at 20 °C is 3.5 hPa.[9] 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.[10] The partition coefficient log POW is measured to −0.85.[11] Since the density of DMF (0.95 g·cm−3 at 20 °C[8]) is similar to that of water, significant flotation or stratification in surface waters in case of accidental losses is not expected.

Left: two resonance structures of DMF. Right: illustration highlighting delocalization.

Reactions

DMF is hydrolyzed by strong acids and bases, especially at elevated temperatures. With sodium hydroxide, DMF converts to formate and dimethylamine. DMF undergoes decarbonylation near its boiling point to give dimethylamine. Distillation is therefore conducted under reduced pressure at lower temperatures.[12]

In one of its main uses in organic synthesis, DMF is a reagent in the Vilsmeier–Haack reaction, which is used to formylate aromatic compounds.[13][14] The process involves initial conversion of DMF to a chloroiminium ion, [(CH3)2N=CH(Cl)]+, known as a Vilsmeier reagent,[15] which attacks arenes.

Organolithium compounds and Grignard reagents react with DMF to give aldehydes after hydrolysis in a reaction called Bouveault aldehyde synthesis.[16]

Dimethylformamide forms 1:1

adducts with a variety of Lewis acids such as the soft acid I2, and the hard acid phenol. It is classified as a hard Lewis base and its ECW model base parameters are EB = 2.19 and CB = 1.31.[17] Its relative donor strength toward a series of acids, versus other Lewis bases, can be illustrated by C-B plots.[18][19]

Production

DMF was first prepared in 1893 by the French chemist Albert Verley (8 January 1867 – 27 November 1959), by distilling a mixture of dimethylamine hydrochloride and potassium formate.[20]

DMF is prepared by combining methyl formate and dimethylamine or by reaction of dimethylamine with carbon monoxide.[21]

Although currently impractical, DMF can be prepared from supercritical carbon dioxide using ruthenium-based catalysts.[22]

Applications

The primary use of DMF is as a solvent with low evaporation rate. DMF is used in the production of

adhesives, synthetic leathers, fibers, films, and surface coatings.[8]

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

Safety

Dimethylformamide vapor exposure has shown reduced alcohol tolerance and skin irritation in some cases.[30]

On 20 June 2018, the

squishies
. The density of the compound in the toy resulted in all squishies being removed from the Danish market. All squishies were recommended to be thrown out as household waste. [31]

Toxicity

The acute

LD50 (oral, rats and mice) is 2.2–7.55 g/kg.[8] Hazards of DMF have been examined.[32]

References

  1. ^ N,N-Dimethylmethanamide, NIST web thermo tables
  2. ISBN 978-0-85404-182-4
    . The traditional name 'formamide' is retained for HCO-NH2 and is the preferred IUPAC name. Substitution is permitted on the –NH2 group.
  3. ^ "Hazardous Substances Data Bank (HSDB) - N,N-DIMETHYLFORMAMIDE".
  4. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0226". National Institute for Occupational Safety and Health (NIOSH).
  5. ^ a b "Dimethylformamide". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  6. ^ a b "Dimethylformamide". Spectral Database for Organic Compounds. Japan: AIST. Retrieved 2012-06-28.[permanent dead link]
  7. doi:10.1063/1.1743184
    .
  8. ^
    ISBN 978-3527306732
    .
  9. ^ IPCS (International Programme on Chemical Safety) (1991). Environmental Health Criteria 114 "Dimethylformamide" United Nations Environment Programme, International Labour Organisation, World Health Organization; 1–124.
  10. S2CID 36740734
    .
  11. ^ (BASF AG, department of analytical, unpublished data, J-No. 124659/08, 27.11.1987)
  12. ISBN 9780470842898
    .
  13. ^
    doi:10.1002/cber.19270600118
    .
  14. ^
    ISBN 9780080405933
    .
  15. doi:10.1002/0471264180.or056.02
    .
  16. ISBN 9780471704508
    .
  17. doi:10.1021/ed073p701
    .
  18. ^ 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
  19. doi:10.1021/ed054p612. The plots shown in this paper used older parameters. Improved E&C parameters are listed in ECW model
    .
  20. ^ Verley, A. (1893). "Sur la préparation des amides en général" [On the preparation of amides in general]. Bulletin de la Société Chimique de Paris. 3rd series (in French). 9: 690–692. On p. 692, Verley states that DMF is prepared by a procedure analogous to that for the preparation of dimethylacetamide (see p. 691), which would be by distilling dimethylamine hydrochloride and potassium formate.
  21. ISBN 3-527-30578-5
    .
  22. ISBN 978-3-527-29605-7
    . Retrieved 27 June 2011.
  23. ^ Bouveault, Louis (1904). "Modes de formation et de préparation des aldéhydes saturées de la série grasse" [Methods of preparation of saturated aldehydes of the aliphatic series]. Bulletin de la Société Chimique de Paris. 3rd series (in French). 31: 1306–1322.
  24. ^ Bouveault, Louis (1904). "Nouvelle méthode générale synthétique de préparation des aldéhydes" [Novel general synthetic method for preparing aldehydes]. Bulletin de la Société Chimique de Paris. 3rd series (in French). 31: 1322–1327.
  25. ISBN 978-3-319-03979-4
    .
  26. ISBN 9780470716069
    .
  27. ISBN 0-19-850346-6
    .
  28. ^ Ansell, M. F. in "The Chemistry of Acyl Halides"; S. Patai, Ed.; John Wiley and Sons: London, 1972; pp 35–68.
  29. ^ Haddon, R.; Itkis, M. (March 2008). "3. Near-Infrared (NIR) Spectroscopy" (pdf). In Freiman, S.; Hooker, S.; Migler; K.; Arepalli, S. (eds.). Publication 960-19 Measurement Issues in Single Wall Carbon Nanotubes. NIST. p. 20. Retrieved 2012-06-28.
  30. PMID 444443
    .
  31. ^ Magnus Løfstedt. "Skumlegetøj afgiver farlige kemikalier (in English- Squishies giving dangerous chemicals)". Archived from the original on 2021-09-03. Retrieved 2019-06-13.
  32. PMID 3358569
    .

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=Dimethylformamide&oldid=1219592542"