600-which takes place during the carbonation reaction has been shown to occur in other instance^.^ However, the introduction of the second carboxyl group in this case is not due to such a reaction, in view of the gradual rise in the percentage of diacids with the time of reaction. A higher ratio of di-to monocarboxylic acids would be expected at the beginning of the reaction, when a larger excess of butyllithium was present, should the formation of ...
