Phase-transfer catalysis history

The history of supramolecular carbene chemistry is not long. Preliminary trials, during the 1970s, involved the generation of carbenes in the presence of micelles, e.g., quaternary ammonium salts, and crown ethers.72 However, carbene host ICs were not formed, nor were they sought. Instead, these hosts enable phase transfer catalysis (PTC) of Lewis acid-Lewis base reactions, e.g., the SN2 reaction (Equation (1)). 

Part II contains four chapters about history, theory, molecular mechanisms, synthesis, and experimental systems in phase transfer catalysis. 

The histories of phase transfer catalysis, Merrifield peptide synthesis, and supported enzymes suggest that synthetic processes using polymeric catalysts may be adopted in commercial production, but that methods for multistep syntheses are less likely. The reasons for this prediction follow. 

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