Three different new insoluble bead-shaped polymer-supported multisite phase transfer catalysts containing two, four and six active sites have been prepared and characterized by FTIR, TGA, [chloride ion] and SEM analyses. The presence of number of active sites in each catalyst and their corresponding catalytic ability were studied by determining pseudo-first order rate constants for C-alkylation of phenylacetonitrile (PAN) and four different substituted PAN as the substrate using a low concentration of NaOH (25% w/w) at 50 degrees C. The observed rate constants were compared with rate constants of same reactions catalyzed by single-site catalyst under identical reaction conditions. From comparative study, the efficiency of catalysts were found to be in the order six-site>four-site>two-site>single-site thus confirming number of active sites in each catalyst. Further, the detailed kinetic profile of C-alkylation of PAN has been investigated using the superior six-site catalyst by varying stiring speed, [substrate], [catalyst], [NaOH], and temperature. Based on the observed kinetic and activation parameters, an interfacial mechanism was proposed. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 771-785, 2009