A periodic mesoporous hybrid material with a built-in palladium complex: An efficient catalyst for the Suzuki coupling and alcohol oxidation

A new periodic mesoporous hybrid material with a built-in Pd–guanidine complex was synthesized in the presence of a structure-directing agent. The N2 sorption, XRD and TEM characterizations revealed that this hybrid material had a large surface area (>700 m2 g−1), a narrow pore size distribution (centered at 2.7 nm), and a periodic 2D-hexagonal structure. FT-IR, solid state NMR and XPS investigations confirmed that palladium–guanidine complex was covalently integrated with the solid material. The solid material exhibited high activity for the Suzuki coupling reaction of various aryl bromides in an aqueous ethanol solution under air. Furthermore, it was found that the solid material worked well for the aerobic oxidation of benzylic alcohols under ambient pressure of O2, affording over 99% selectivity. This catalyst could be reused 9 times without a decrease in selectivity. This study supplies a new periodic mesoporous hybrid material with a built-in active palladium sites, which may be applied to other catalytic reactions.

Graphical abstractA new periodic mesoporous hybrid material with a built-in Pd–guanidine complex has been synthesized in the presence of a structure-directing agent. The synthesized solid material exhibited high activity and recyclability for the Suzuki coupling reactions of various aryl bromides in air and the aerobic oxidation of benzylic alcohols under ambient pressure of O2.Figure optionsDownload full-size imageDownload high-quality image (99 K)Download as PowerPoint slide