How iodide anions inhibit the phase-transfer catalyzed reactions of carbanions

The inhibitory effect of iodide anions on the phase-transfer catalyzed reactions of carbanions generated in liquid–liquid two-phase systems by aqueous NaOH is due to preferential location of these anions in the interfacial region of the two-phase system—organic phase/concd aqueous NaOH. In such situation, the basic activity of NaOH in this region is decreased and the equilibrium of deprotonation of the carbanion precursors is disfavoured.