| content | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Maleic anhydride | |
|---|---|
 |
 |
| IUPAC name | Maleic anhydride |
| Identifiers | |
| CAS number | [108-31-6] |
| RTECS number | UE5950000 |
| SMILES |
|
| Properties | |
| Molecular formula | C4H2O3 |
| Molar mass | 98.06 g/mol |
| Appearance | white crystals |
| Density | 1.314 g/cm3 |
| Melting point |
60 °C, 333 K, 140 °F |
| Boiling point |
202 °C, 475 K, 396 °F |
| Solubility in water | 40 g/100 ml at ? °C |
| Hazards | |
| MSDS | MSDS at J. T. Baker |
| EU classification | Corrosive (C) |
| NFPA 704 |
 1
3
1
|
| R-phrases | R22, R34, R42/43 |
| S-phrases | (S2), S22, S26, S36/37/39, S45 |
| Flash point | 102 °C |
| Related compounds | |
| Related acid anhydrides | Succinic anhydride |
| Related compounds | Maleic acid |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
|
Maleic anhydride (cis-butenedioic anhydride, toxilic anhydride, dihydro-2,5-dioxofuran) is an organic compound with the formula C4H2O3. In its pure state it is a colourless or white solid with an acrid odour.
Maleic anhydride was traditionally manufactured by the oxidation of benzene or other aromatic compounds. As of 2006, only few smaller plants continue to use benzene; due to rising benzene prices, most maleic anhydride plants now use n-butane as a feedstock:
- 2 CH3CH2CH2CH3 + 7 O2 → 2 C2H2(CO)2O + 8 H2O
Characteristic reactions
The chemistry of maleic anhydride is very rich, reflecting its ready availability and bifunctional reactivity.
- It hydrolyzes, producing maleic acid, cis-HO2CCH=CHCO2H. With alcohols, the half-ester is generated, e.g., cis-HO2CCH=CHCO2CH3.
- Maleic anhydride is a potent dienophile in Diels-Alder reactions.
- Maleic anhydride (MA) is an excellent ligand for low-valent metal complexes, examples being Pt(PPh3)2(MA) and Fe(CO)4(MA).
References
 |
This article does not cite any references or sources. (September 2007) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
External links
- International Chemical Safety Card 0799
- NIOSH Pocket Guide to Chemical Hazards 0376
- Chronic toxicity summary
- Maleic anhydride at Occupational Safety & Health Administration
