A palladium-based catalyst supported on acac-functionalized silica was used as a heterogeneous catalyst for the Sonogashira cross-coupling reaction of various aryl halides and phenylacetylene under copper-and phosphine-free conditions. This catalytic system serves as an efficient and stable catalyst for this cross-coupling reaction and allows easy separation and recycling of the catalyst. The catalyst could be recycled for five runs without appreciable loss of its catalytic activity. In addition, the reaction was carried out in water as a green solvent.

The preparation of palladium nanoparticles supported on acetylacetone‐modified silica gel and their catalytic application for Heck olefination of aryl halides were investigated. The catalyst was characterized using X‐ray diffraction, X‐ray photoelectron spectroscopy, and transmission and scanning electron microscopies. The supported palladium nanoparticles are demonstrated to be a highly active and reusable catalyst for the Heck reaction. Several reaction parameters, including type and amount of solvent and base, were evaluated. The heterogeneity of the catalytic system was investigated with results indicating that there is a slight palladium leaching into the reaction solution under the applied reaction conditions. Despite this metal leaching, the catalyst can be reused nine times without significant loss of catalytic activity. Copyright © 2015 John Wiley & Sons, Ltd.

Supported Pd nanoparticles on acetyl acetone modified silica gel was prepared and its catalytic application in the Suzuki-Miyaura reaction of various aryl halides with phenylboronic acid was investigated. The reaction was carried out in water as solvent under green conditions in the presence of NaHCO 3 as the base. The catalyst was characterized by a combination of powder XRD, XPS, TEM and SEM. The catalyst is not sensitive to air and moisture, so reactions were carried out without using inert atmosphere. The catalyst can be reused up to six times without significant loss of catalyst activity. The cumulative turnover number (TON) over six runs is 13525.

Silica-(acac)-Supported Palladium Nanoparticles in Water. -Catalyst can be recycled and reused up to 5 times without appreciable loss in its activity. -(HAJIPOUR*, A. R.; SHIRDASHTZADE, Z.; AZIZI, G.; Appl. Organomet. Chem. 28 (2014) 9, 696-698, http://dx.doi.org/10.1002/aoc.3184 ; Dep. Chem., Isfahan Univ. Technol., Isfahan 84156, Iran; Eng.) -M. Tismer 07-130

Water. -The catalyst can be reused up to six times without significant loss of its catalytic activity. -(HAJIPOUR*, A. R.; SHIRDASHTZADE, Z.; AZIZI, G.; J. Chem. Sci. (Bangalore, India) 126 (2014) 1, 85-93, http://dx.