Reactions of some dicarbonyl compounds. Part III. Oxidation of some β-diketones with alkaline hydrogen peroxide

Abstract

Oxidation of β-diketones (R¹CO·CR²R³·COR⁴) with alkaline hydrogen peroxide affords two types of acid depending upon the nature of R² and R³. Where both of these are H, the products are R¹CO₂H, R⁴CO₂H, and formic acid, which suffers further oxidation. Where R² is alkyl, the products are R¹CO₂H, R²CO₂H, R⁴CO₂H, and R¹R²CH·CO₂H and/or R²R⁴CH·CO₂H. Where both R² and R⁴ are alkyl, the products are R¹R²R³C·CO₂H and R⁴CO₂H, and R²R³R⁴C·CO₂H and R¹CO₂H, and this constitutes a useful source of trisubstituted acetic acids. The mechanisms of these reactions are discussed, and an additional oxidative side-reaction of two 2-alkyl-1,3-diketones is described.