Acetic formic anhydride

Acetic formic anhydride is an organic compound with the chemical formula C
₃H
₄O
₃, which can be viewed as the mixed anhydride of acetic acid and formic acid. It is used on a laboratory-scale as a formylating agent.^[1]

Acetic formic anhydride

Names
Preferred IUPAC name Acetic formic anhydride
Other names Acetyloxymethanone Formyl acetate Formic acetic anhydride ethanoic methanoic anhydride
Identifiers
CAS Number	2258-42-6 N
3D model (JSmol)	Interactive image
ChemSpider	67812 Y
PubChem CID	75269
CompTox Dashboard (EPA)	DTXSID80177103
InChI InChI=1S/C3H4O3/c1-3(5)6-2-4/h2H,1H3 Y Key: ORWKVZNEPHTCQE-UHFFFAOYSA-N Y
SMILES CC(=O)OC=O
Properties
Chemical formula	C3H4O3
Molar mass	88.062 g·mol−1
Appearance	colourless liquid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation

Acetic formic anhydride can be produced by reacting sodium formate with acetyl chloride in anhydrous diethyl ether between 23–27 °C.^[2] It can also be prepared by the reaction of acetic anhydride and formic acid at 0 °C.

Properties

While more stable than formic anhydride, acetic formic anhydride is thermally unstable and gradually decomposes above about 60 °C, with the evolution of carbon monoxide.^[3] Impurities such as pyridine or residual acid can promote this, resulting in decomposition commencing as low as 0 °C. Crude material has been successfully purified by distillation at ≤30 °C under reduced pressure.^[3]

Applications

Acetic formic anhydride is a formylation agent for amines, amino acids, and alcohols. It is also a starting material for other compounds such as formyl fluoride.^[2][1]

See also

• Formic anhydride
• Acetic anhydride
• Acetic oxalic anhydride