The cobalt-catalyzed conversion of methyl formate into acetic acid

Article abstract of DOI:10.1016/0022-328X(91)83147-V

Methyl formate can be selectively converted into acetic acid in quantitative yield by use of cobalt catalysts.Essential requirements include the presence of a tertiary amide as solvent, of an ionic iodide as promoter, a sufficiently high CO pressure (above 100 bar), and a reaction temperature between 160 deg and 180 deg C.Other alkyl formates are not transformed into acids.The reaction probably involves, as the key step, the reduction of the cobalt(II) catalyst to a cobaltate species, which is then transformed into alkyl and acylcobalt species.The latter reacts with lithium formate, formed in situ, to afford a mixed anhydride, decarbonylation of which yields acetic acid with regeneration of CO.