Silica-acac-supported palladium nanoparticles as an efficient and reusable heterogeneous catalyst in the Suzuki–Miyaura cross-coupling reaction in water

Abstract

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–acetylacetone‐supported palladium nanoparticles as an efficient and reusable catalyst in the Heck–Mizoroki C–C cross‐coupling reaction

“…In continuation of our recent investigations of the synthesis and application of SiO 2 ‐acac‐PdNPs in carbon–carbon cross‐coupling reactions, we now report the extension of the use of this heterogeneous nano‐catalyst for the cross‐coupling reaction of olefins with various aryl halides (Scheme ).…”

Copper‐ and phosphine‐free Sonogashira coupling reaction catalyzed by silica–(acac)‐supported palladium nanoparticles in water

“…In continuation of our recent investigations of the synthesis and application of SiO 2 ‐acac‐PdNPs in carbon–carbon cross‐coupling reactions, we now report the extension of this heterogeneous nanocatalyst for the cross‐coupling reaction of phenylacetylene with various aryl halides under copper‐ and phosphine‐free conditions (Scheme ).…”

“…The catalyst was synthesized according to previous work . In summary, acid‐activated silica gel was dried at 150°C overnight and cooled in a desiccator.…”

Suzuki–Miyaura reaction by heterogeneously supported Pd in water: recent studies

“…Supported Pd nanoparticles on an acetyl acetone modied silica gel (catalyst 81) were prepared (Scheme 89), and the catalytic application in the Suzuki-Miyaura reaction of various aryl halides with phenylboronic acid was investigated (Scheme 90). 94 The amount of Pd on the catalyst was 0.04 mmol g À1 (4.26 mg g À1 ) determined using AAS. The TEM image indicated the presence of palladium nanoparticles in the range of 6-12 nm.…”