Alkoxycarbonyl- and Carboxylate-Group Migrations in the Benzilic Acid Rearrangement of Ethyl Cyclopropane-2,3-dioxopropionate

Article abstract of DOI:10.1002/hlca.19820650813

In alkaline medium C3H5-CO-C(OH)2-COOEt (1b) is transformed into C3H5-C(OH)2(COOH)2 (2a).Labelling experiments show that the cyclopropyl group is not shifted, but only ROOC and/or ^-O2C groups.GC./MS. and NMR analysis after incomplete reaction show that both ROOC- and ^-O2C-groups migrate; at higher pH (ca. 14) the ester group rearrangement seems to be more important than at pH ca. 9-10.