Oxyfunctionalization of Active Methylene Compounds Using Sodium Chlorite in Water

Abstract

AbstractA methylene group inserted between proximal carbonyl groups underwent exclusive oxyfunctionalization with sodium chlorite in the presence of redox‐inert HfIV in water. Direct oxidation methods have conventionally suffered from manifold side reactions such as oxidative fragmentation, dimerization, and overreactions, together with the use of toxic and intractable oxidants. Although alternative routes involving prior α‐functionalization can be executed under mild conditions, preparatively valuable oxidation methods that deliver high levels of both conversion and selectivity remain a prized goal from the standpoint of streamlining organic synthesis. Chlorine dioxide, which was generated as a yellowish gas during the reaction, is considered to be a bona fide oxidant against active methylene compounds. The pivotal role of water was clear, given that the reaction was significantly retarded in both aqueous acetonitrile and ethanol, which can solubilize sodium chlorite.