Dimethyl acetylenedicarboxylate

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Dimethyl acetylenedicarboxylate
Chemical structure of DMAD
General
Systematic name Dimethyl
acetylenedicarboxylate
Other names DMAD
Acetylenedicarboxylic
acid, dimethyl ester
Molecular formula C6H6O4
SMILES O=C(OC)C#CC(OC)=O
Molar mass 142.11 g/mol
Appearance Colorless liquid
CAS number [762-42-5]
Properties
Density and phase 1.1564 g/cm3
Solubility in water Insoluble
Other solvents Soluble in most
organic solvents
Melting point -117 °C
Boiling point 195–198 °C
96–98° at 8 mm Hg
Structure
Dipole moment 0 D
Hazards
MSDS External MSDS
Main hazards Toxic gas
NFPA 704
Flash point 187 °F
R/S statement R: R34
S: S23 S26 S27
S36/37/39 S45
RTECS number ES0175000
Supplementary data page
Structure and
properties
n = 1.447
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Related compounds
Related compounds Methyl propiolate,
Hexafluoro-2-butyne,
Acetylene
Except where noted otherwise, data are given for
materials in their standard state (at 25 °C, 100 kPa)
Infobox disclaimer and references

Dimethyl acetylenedicarboxylate (DMAD) is the organic compound with the formula CH3O2CC2CO2CH3. This alkyne, which exists as a liquid at room temperature, is highly electrophilic. As such, DMAD, as it is commonly called in the laboratory, is widely employed as a dienophile in cycloaddition reactions, such as the Diels-Alder reaction. It is also a potent Michael acceptor.[1]

Contents

[edit] Preparation

Although inexpensively available, DMAD is prepared today as it was originally.[2] Maleic acid is brominated and the resulting dibromosuccinic acid is dehydrohalogenated.[3] The dicarboxylic acid is then esterified with methanol and sulfuric acid as a catalyst.[4]

[edit] Safety

DMAD is a lachrymator and a vesicant.

[edit] 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: 10.1002/047084289.
  2. ^ Bandrowski, E. “Ueber Acetylendicarbonsäure” Chemische Berichte band 10, 838 (1877).
  3. ^ Abbott, T. W.; Arnold, R. T.; Thompson, R. B. “Acetylenedicarboxyltic acid” Organic Syntheses, Collective Volume 2, page 10.
  4. ^ Huntress, E. H. Lesslie, T. E.; Bornstein, J. “Dimethyl Acetylenedicarboxylate” Organic Syntheses, Collective Volume 4, page 329.

[edit] External links