Inorganic methylene/methine compounds

The representative reaction system applied in asymmetric phase-transfer catalysis is the biphasic system composed of an organic phase containing an acidic methylene or methine compound and an electrophile, and an aqueous or solid phase of inorganic base such as alkaline metal (Na, K, Cs) hydroxide or carbonate. The key reactive intermediate in this type of reaction is the onium carbanion species, mostly onium enolate or nitronate, which reacts with the electrophile in the organic phase to afford the product. 

Phase-Transfer Reaction of Active Methylene or Methine Compounds with inorganic Base... 

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