Hollow-shell-structured mesoporous silica-supported palladium catalyst for an efficient Suzuki-Miyaura cross-coupling reaction

Abstract

The construction of a high stability heterogeneous catalyst for privileged common catalysis is a benefit in regard to reuse and separation. Herein, a palladium diphenylphosphine-based hollow-shell-structured mesoporous catalyst (HS@PdPPh2@MSN) was prepared by immobilizing bis((diphenylphosphino)ethyltriethoxysilane)palladium acetate onto the inner wall of a mesopo-rous organicsilicane hollow shell, whose surface was protected by a –Si(Me)3 group. Electron mi-croscopies confirmed its hollow-shell-structure, and structural analyses and characterizations re-vealed its well-defined single-site active species within the silicate network. As presented in this study, the newly constructed HS@PdPPh2@MSN enabled an efficient Suzuki-Miyaura cross-cou-pling reaction for varieties of substrates with up to 95% yield in mild conditions. Meanwhile, it could be reused at least five times with good activity, indicating its excellent stability and recyclability. Furthermore, the cost-effective and easily synthesized HS@PdPPh2@MSN made it a good candidate for employment in fine chemical engineering.