The rearrangement of ethyl 2-hydroxyindoxyl-2-carboxylate to ethyl 3-hydroxyoxindole-3-carboxylate
Abstract
Ethyl 2-hydroxyindoxyl-2-carboxylate with aqueous sodium hydroxide rearranges to ethyl 3-hydroxyoxindole-3-carboxylate with a sufficiently low incorporation of 18O from the solvent to establish that ring-opening does not precede the ester shift.