Maleic anhydride



Maleic anhydride
IUPAC name Maleic anhydride
Identifiers
CAS number 108-31-6
RTECS number UE5950000
SMILES O=C1C=CC(=O)O1
Properties
Molecular formula C4H2O3
Molar mass 98.06 g/mol
Appearance white crystals
Density 1.314 g/cm3
Melting point

53 °C, 326 K, 127 °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 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 butane as a feedstock. As of 2006, only few smaller plants continue to use benzene:

CH3CH2CH2CH3 + 3.5 O2 → C2H2(CO)2O + 4 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 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 is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Maleic_anhydride". A list of authors is available in Wikipedia.