In 1971 Charles M. Starks first coined the term "phase transfer catalysis". This term describes a solution to the problem of heterogeneity arises when the reaction substances are in different phases of the reaction mixture.

Traditionally this problem was solved by removing the right mutual solvent, but by adding a small amount of the agent which transfers one reactant across the interface into the other, the reaction may proceed smoothly even in the case of a heterogeneous phase system.

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 Starks found that soluble organic ammonium or phosphonium cations, Q +, is a suitable agent for the transport of anions from the aqueous phase to the organic phase.

The focus of phase transfer catalyst has been mainly in the structure such as prochiral protected glycine derivative and malonates, and less attention has been paid to the substrate with a higher pKa.

Because of all the research that discusses the types of phase transfer catalysis is from the early 1980s until the early 1990s, it would be better to evaluate the category of catalysts that have been developed since then.

Phase Transfer Catalysis (PTC) is used as part of commercial manufacturing of more than $ 10 billion of chemicals each year. PTC is also used as part of pollution prevention, treatment and to remove impurities in the waste and product streams.

Demand from PTC increases in the chemical industry because of several advantages assured supply, mainly to reduce costs in the manufacture of organic chemicals and pollution prevention.