Dimethyl acetylenedicarboxylate

Dimethyl acetylenedicarboxylate
Chemical structure of DMADuak
Ball-and-stick model
Names
Preferred IUPAC name
Dimethyl but-2-ynedioate
Other names
DMAD
Acetylenedicarboxylic
acid dimethyl ester
Identifiers
CAS Number
  • 762-42-5 checkY
3D model (JSmol)
  • Interactive image
ChEMBL
  • ChEMBL3248452
ChemSpider
  • 12440 checkY
ECHA InfoCard 100.010.999 Edit this at Wikidata
EC Number
  • 212-098-4
PubChem CID
  • 12980
RTECS number
  • ES0175000
UNII
  • 7HZA2PL15F
CompTox Dashboard (EPA)
  • DTXSID0061088 Edit this at Wikidata
InChI
  • InChI=1S/C6H6O4/c1-9-5(7)3-4-6(8)10-2/h1-2H3 checkY
    Key: VHILMKFSCRWWIJ-UHFFFAOYSA-N checkY
  • InChI=1/C6H6O4/c1-9-5(7)3-4-6(8)10-2/h1-2H3
    Key: VHILMKFSCRWWIJ-UHFFFAOYAX
  • COC(=O)C#CC(=O)OC
Properties
Chemical formula
 C6H6O4
Molar mass 142.11 g/mol
Appearance Colorless liquid
Density 1.1564 g/cm3
Melting point −18 °C (0 °F; 255 K)
Boiling point 195 to 198 °C (383 to 388 °F; 468 to 471 K) (96–98° at 8 mm Hg)
Solubility in water
 Insoluble
Solubility in other solvents Soluble in most
organic solvents
Refractive index (nD)
 1.447
Structure
Dipole moment
 0 D
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Toxic
GHS labelling:
GHS05: CorrosiveGHS07: Exclamation mark
Danger
H302, H314
P260, P264, P270, P280, P301+P312, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P330, P363, P405, P501
Flash point 187 °C (369 °F; 460 K)
Related compounds
Related compounds
 Methyl propiolate,
Hexafluoro-2-butyne,
Acetylene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Chemical compound

Dimethyl acetylenedicarboxylate (DMAD) is an organic compound with the formula CH3O2CC2CO2CH3. It is a di-ester in which the ester groups are conjugated with a C-C triple bond. As such, the molecule is highly electrophilic, and is widely employed as a dienophile in cycloaddition reactions, such as the Diels-Alder reaction. It is also a potent Michael acceptor.[1][2] This compound exists as a colorless liquid at room temperature. This compound was used in the preparation of nedocromil.

Preparation

Although inexpensively available, DMAD is prepared today as it was originally. Maleic acid is brominated and the resulting dibromosuccinic acid is dehydrohalogenated with potassium hydroxide yielding acetylenedicarboxylic acid.[3][4] The acid is then esterified with methanol and sulfuric acid as a catalyst:[5]

Safety

DMAD is a lachrymator and a vesicant.[citation needed]

References

  1. ^ Stelmach, J. E.; Winkler, J. D. "Dimethyl Acetylenedicarboxylate"in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi:10.1002/047084289X.
  2. ^ Sahoo, Manoj (2007). "Dimethyl Acetylene Dicarboxylate". Synlett. 2007 (13): 2142–2143. doi:10.1055/s-2007-984894.
  3. ^ Bandrowski, E. (1877). "Ueber Acetylendicarbonsäure". Berichte der Deutschen Chemischen Gesellschaft. 10: 838–842. doi:10.1002/cber.187701001231.
  4. ^ Abbott, T. W.; Arnold, R. T.; Thompson, R. B. (1938). "Acetylenedicarboxylic acid". Organic Syntheses. 18: 3. doi:10.15227/orgsyn.018.0003; Collected Volumes, vol. 2, p. 10.
  5. ^ Huntress, E. H.; Lesslie, T. E.; Bornstein, J. (1952). "Dimethyl Acetylenedicarboxylate". Organic Syntheses. 32: 55. doi:10.15227/orgsyn.032.0055; Collected Volumes, vol. 4, p. 329.