Acetic oxalic anhydride

Acetic oxalic anhydride
Identifiers
CAS number	19037-85-5
ChemSpider	25991421
Jmol-3D images	Image 1
SMILES CC(OC(C(OC(C)=O)=O)=O)=O
InChI InChI=1S/C6H6O6/c1-3(7)11-5(9)6(10)12-4(2)8/h1-2H3 Key: XRMBFFGBVGXJJF-UHFFFAOYSA-N
Properties
Molecular formula	C6H6O6
Molar mass	174.11 g mol−1
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Acetic oxalic anhydride is an organic compound with formula C₆H₆O₆ or (H₃C-(C=O)-O-(C=O)-)₂. It can be viewed as a mixed anhydride, formally derived from acetic acid (H₃C-(C=O)OH) and oxalic acid ((-(C=O)OH)₂), in 2:1 molecular ratio, by the loss of two water molecules.

It is an unstable colorless crystalline solid, soluble in diethyl ether, that decomposes at about -3 °C into acetic anhydride (H₃C-(C=O)-)₂O, carbon dioxide (CO₂) and carbon monoxide (CO). It is hydrolyzed by water into acetic and oxalic acids.^[1]

Unlike some other anhydrides, it cannot be obtained directly from the acids. It was synthesized in 1953 by W. Edwards and W. M. Henley, by reacting silver oxalate (Ag₂C₂O₄) suspended in diethyl ether with acetyl chloride at temperatures below -5°C and distilling off the solvent under low pressure. It can also be obtained by reacting anhydrous oxalic acid with ketene (H₂C=O=O).^[1]

Acetic oxalic anhydride was conjectured to be an intermediate in the decomposition of anhydrous oxalic acid by acetic anhydride.^[1]

See also

• Oxalic anhydride

References

1. ^ ^{a b c} W. R. Edwards and Walter M. Henley (1953), Acetic Oxalic Anhydride. J. Am. Chem. Soc., volume 75, issue 14, pages 3857-3859. doi:10.1021/ja01110a505