Heterogeneous Sonogashira Coupling over Nanostructured SiliaCat Pd(0)

Abstract

Sol–gel entrapped catalyst SiliaCat Pd(0) heterogeneously mediates the Sonogoashira coupling of different aryl halides and phenylacetylene either under thermal conditions or, much more efficiently, under microwave irradiation, affording good conversions of coupled products. Leaching of valued Pd is limited, and the catalyst can be reused

Palladium supported on bis(indolyl)methane functionalized magnetite nanoparticles as an efficient catalyst for copper-free Sonogashira-Hagihara reaction

“…The palladium catalyzed carbon-carbon bond forming reactions are of great importance in modern synthetic organic chemistry [1]. Among well-known carbon-carbon coupling reactions, the Sonogashira-Hagihara cross-coupling stands out as a unique method enabling the coupling between (sp) carbon and (sp 2 ) carbon atoms [2][3][4][5][6][7][8][9]. The reaction products containing such bonds have found applications in a wide range of synthetic reactions such as biologically active compounds and pharmaceuticals [10][11][12].…”

Solid-Supported Palladium Catalysts in Sonogashira Reactions: Recent Developments

“…The hot filtration test suggested a homogeneous reaction pathway, in which the silica material acted as a reservoir of the palladium species that reacted in the solution. Sol-gel entrapped SiliaCat, an organoceramic matrix with high catalyst loading and surface area, containing PdNPs (0.1 mol%) has shown to promote the copper-free Sonogashira reaction between phenylacetylene and aryl iodides, using potassium carbonate as base in refluxing ethanol or methanol, achieving, after 0.5 h to 3 h, the corresponding products in quantitative yields [90]. When o-iodomethylbenzene was used as substrates under similar reaction conditions, only a 77% yield was obtained.…”

Supramolecular photocatalyst of Palladium (II) Encapsulated within Dendrimer on TiO2 nanoparticles for Photo‐induced Suzuki‐Miyaura and Sonogashira Cross‐Coupling reactions

“…It should be noted that there are many reports of cross-coupling reactions catalyzed via homogeneous or heterogeneous processes, but most of them need to be conducted at elevated temperatures (≥100°C), even under reflux conditions. [53][54][55][56][57][58][59][60][61][62] This study shows that visible light irradiation can drive the same reactions on the Pd (II) [PTATAD] @ TiO 2 under much milder reaction conditions (27-30°C), achieving good to excellent yields, and no additional additives such as cocatalysts or phosphine ligands are required.…”

“…These results proposed that the improved photoactivity predominantly benefits from the synergistic effects of Pd (II) amine‐terminated poly (triazine‐triamine) dendritic on TiO 2 nanoparticles that cause efficient separation and photogenerated electron–hole pairs and photoredox capability of nanocatalyst which all of these advantages due to the tuning of band gap of catalyst in the visible light region. It should be noted that there are many reports of cross‐coupling reactions catalyzed via homogeneous or heterogeneous processes, but most of them need to be conducted at elevated temperatures (≥100 °C), even under reflux conditions . This study shows that visible light irradiation can drive the same reactions on the Pd (II) [PTATAD] @ TiO 2 under much milder reaction conditions (27–30 °C), achieving good to excellent yields, and no additional additives such as co‐catalysts or phosphine ligands are required.…”