Formic anhydride

Formic anhydride
IUPAC name Formyloxymethanone
Other names Methanoic anhydride
Identifiers
CAS number	1558-67-4 Y
PubChem	9548680
ChemSpider	7827603 Y
ChEBI	CHEBI:36657
Beilstein Reference	1901016
Gmelin Reference	1041427
Jmol-3D images	Image 1
SMILES O=COC=O
InChI InChI=1S/C2H2O3/c3-1-5-2-4/h1-2H Y Key: VGGRCVDNFAQIKO-UHFFFAOYSA-N Y
Properties
Molecular formula	C2H2O3
Molar mass	74.04 g mol−1
Exact mass	74.000393930 g mol-1
Appearance	Colorless gas
Boiling point	24 °C, 297 K, 75 °F (at 20 mmHg)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Formic anhydride, also called methanoic anhydride, is a chemical compound with formula C₂H₂O₃ or (H(C=O)-)₂O. It can be viewed as the anhydride of formic acid (HCOOH).

Formic anhydride is a liquid with boiling point 24 °C at 20 mmHg.^[1] It is stable in diethyl ether solution. It can be isolated by low-temperature, low-pressure distillation, but decomposes on heating above room temperature.^[1] It decomposes into formic acid and carbon monoxide. ^[2]

Formic anhydride can be obtained by reaction of formyl fluoride with sodium formate in ether at −78 °C.^[3] It can also be produced by reacting formic acid with N,N′-dicyclohexylcarbodiimide ((C₆H₁₁-N=)₂C) in ether at -10 °C.^[1] It can also be obtained by disproportionation of acetic formic anhydride.^[4]

The decomposition of formic anhydride may be catalyzed by formic acid.^[1]

Formic anhydride can be detected in the gas phase reaction of ozone with ethylene.^[5] The molecule is planar in the gas phase.^[1]

See also

• Acetic formic anhydride
• Acetic anhydride
• Formaldehyde

References

1. ^ ^{a b c d e} G. Wu, S. Shlykov, F. S. Van Alseny, H. J. Geise, E. Sluyts, B. J. Van der Veken (1995), Formic Anhydride in the Gas Phase, Studied by Electron Diffraction and Microwave and Infrared Spectroscopy, Supplemented with Ab-Initio Calculations of Geometries and Force Fields. J. Phys. Chem., volume 99, issue 21, pages 8589–8598 doi:10.1021/j100021a022
2. ^ Boogaard, A.; H. J. Geise and F. C. Mijlhoff (July 1972). "An electron diffraction investigation of the molecular structure of formic anhydride". Journal of Molecular Structure (Elsevier Science) 13 (1): 53–58. doi:10.1016/0022-2860(72)87031-5. http://www.sciencedirect.com/science/article/pii/0022286072870315. Retrieved 9 September 2011. 
3. ^ George A. Olah, Yashwant D. Vankar; Massoud Arvanaghi; Jean Sommer (1979), Formic Anhydride. Angewandte Chemie Int. Ed. Engl., volume 18, issue = 8, page = 614. doi:10.1002/anie.197906141.
4. ^ R. Schijf, J. W. Scheeren, A. van Es, W. Stevens (1965) Mixed carboxylic acid anhydrides: IV. formic anhydride. Recueil des Travaux Chimiques des Pays-Bas, volume 84, issue 5, pages 594–596. doi:10.1002/recl.19650840510
5. ^ A. Vaccani, A. Bauder and Hs. H. Günthar (1975), The Microwave Spectrum of Formic Anhydride. Abstracts of OSU International Symposium on Molecular Spectroscopy 1970-1979