Multiphasic Reactions General Features, Scope, and Limitations

Multiphasic Reactions General Features, Scope, and Limitations 

It is important to make the distinction between the multiphasic catalysis concept and transfer-assisted organometallic reactions or phase-transfer catalysis (PTC). In this latter approach, a catalytic amount of quaternary ammonium salt [Q] [X] is present in an aqueous phase. The catalyst s lipophilic cation [Q] transports the reactant s anion [Y] to the organic phase, as an ion-pair, and the chemical reaction occurs in the organic phase of the two-phase organic/aqueous mixture [2]. 

Since then, water has emerged as a useful solvent for organometallic catalysis. In addition to the hydroformylation reactions, several other industrial processes 

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