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Kinetics of phase-transfer catalysed (PTC'd) dehydrochlorination of the r-isomer of hexachlorocyclohexane in the presence of proton donors was investigated. Carboxylic acids and picric acid act as inhibitors. Benzyl alcohol strongly promotes the reaction. The plots of observed rate constants vs phenol and pentachlorophenol concentration have a bell-shaped form that was not observed before. An example of long-chain quats application in the synthesis of the ketamine anaesthetic intermediate by dehydrochlorination in dilute alkali is shown. Another application of phase-transfer catalysis (PTC) in organochlorine chemistry is the aqueous (sodium hypochlorite) chlorination of alkyl aromatic compounds. The results of m-phenoxytoluene chlorination and reaction kinetics in the presence of the polymeric crown are described.

The results of pilot plant experiments on phase-transfer-catalysed dehydrochlorination of hexachlorocyclohexane and vitamin A manufacturing using phase-transfer catalysis are discussed. A long-chain cationic surfactant (Katamine AB) was a suitable catalyst in these cases. Phase-transfer catalysis is shown to provide advantageous process results and characteristics for these two commercially important reactions under scaled up conditions.