New palladium(II) complexes (2), bearing NHC/TPPTS ligands, (NHC = benzimidazol-2-ylidene; TPPTS = triphenylphosphine-3,3',3 ''-trisulfonic acid trisodium salt) have been prepared and characterized by elemental analyses and spectroscopic methods. Their ability to catalyze the Suzuki-Miyaura reaction in neat water has been studied at 100 degrees C. Very high activities have been observed in the coupling of phenylboronic acid with aryl chlorides in the presence of 1% of the catalyst. We have compared the electronic properties of cis-[PdBr2(NHC)(TPPTS)] with the related complexes, [PdX2(NHC)](2) and [trans-PdBr2(NHC)(pdca)](Pdca = pyridine-2,6-dicarboxyic acid) (3) via three different techniques: cyclic voltammetry, thermogravimetric analysis and C-13 NMR spectroscopy. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.