Formic Anhydride
Support of our work by the National Institutes of Health and the National Science Foundation is gratefully acknowledged, as is a Senior U.S. Scientist Award of the Alexander von Humboldt foundation to G. A. O. facilitating this research.
Formic anhydride (1), the parent carboxylic acid anhydride, has long eluded preparation and characterization. Olah et al.[1] first reported in 1955 the possible formation of (1) in the reaction of formyl fluoride with metal formates at low temperature. No spectroscopic observations or physical data were, however, obtained. In 1964. Muramatsu et al.[2] assumed the intermediacy of (1) in the formylation of p-nitrophenol and L-leucine with an ethereal solution of formic acid and dicyclohexylcarbodiimide (DCC); no isolation was attempted nor were physical data obtained. Stevens et al.[3], in the same year, reported the formation of (1) by the thermal disproportionation of formic-acetic anhydride and of mixtures of formic acid and carboxylic anhydrides; proof of formation of (1) was based on the appearance of a 1H-NMR singlet at δ = 9.0, which, however, might have been due to a mixed anhydride or other species…
