Dimethyl acetylenedicarboxylate
From Wikipedia, the free encyclopedia
| Dimethyl acetylenedicarboxylate | |
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| IUPAC name | Dimethyl acetylenedicarboxylate |
| Other names | DMAD Acetylenedicarboxylic acid, dimethyl ester |
| Identifiers | |
| CAS number | [762-42-5] |
| RTECS number | ES0175000 |
| SMILES | O=C(OC)C#CC(OC)=O |
| Properties | |
| Molecular formula | C6H6O4 |
| Molar mass | 142.11 g/mol |
| Appearance | Colorless liquid |
| Density | 1.1564 g/cm³ |
| Melting point |
-117 °C |
| Boiling point |
195–198 °C |
| Solubility in water | Insoluble |
| Solubility in other solvents | Soluble in most organic solvents |
| Refractive index (nD) | 1.447 |
| Structure | |
| Dipole moment | 0 D |
| Hazards | |
| Main hazards | Toxic gas |
| R-phrases | R34 |
| S-phrases | S23 S26 S27 S36/37/39 S45 |
| Flash point | 187 °F |
| 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 |
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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][2]
[edit] Preparation
Although inexpensively available, DMAD is prepared today as it was originally.[3] Maleic acid is brominated and the resulting dibromosuccinic acid is dehydrohalogenated.[4] The dicarboxylic acid is then esterified with methanol and sulfuric acid as a catalyst.[5]
[edit] Safety
DMAD is a lachrymator and a vesicant.
[edit] References
- ^ 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.
- ^ Sahoo, Manoj Kumar: Dimethyl Acetylene Dicarboxylate SYNLETT 2007, No. 13, pp 2142–2143 doi:10.1055/s-2007-984894 Open access
- ^ Bandrowski, E. “Ueber Acetylendicarbonsäure” Chemische Berichte band 10, 838 (1877).
- ^ Abbott, T. W.; Arnold, R. T.; Thompson, R. B. “Acetylenedicarboxyltic acid” Organic Syntheses, Collective Volume 2, page 10.
- ^ Huntress, E. H. Lesslie, T. E.; Bornstein, J. “Dimethyl Acetylenedicarboxylate” Organic Syntheses, Collective Volume 4, page 329.
