Multiple Functionalized Hyperbranched Polyethoxysiloxane Promotes Suzuki Coupling Asymmetric Transfer Hydrogenation One-Pot Enantioselective Organic Transformations

作者：Zhang, Genwei; Liu, Rui; Chou, Yajie; Wang, Yu; Cheng, Tanyu; Liu, Guohua^*

来源：ChemCatChem, 2018, 10(8): 1882-1888.

DOI：10.1002/cctc.201701256

• asymmetric catalysis
• biaryls
• immobilization
• polymers
• mesoporous materials

Utilization of amphiphilic poly(ethylene glycol) monomethyl ether modified hyperbranched polyethoxysiloxane as a support for the construction of bifunctional heterogeneous catalysts enables a highly efficient catalytic system thanks to its amphiphilic nature in aqueous organic transformations. Herein, through a three-component self-assembly procedure, we incorporate palladium/phosphine and chiral ruthenium/diamine functionality within poly(ethylene glycol) monomethyl ether modified hyperbranched polyethoxysiloxane, fabricating a multiple functionalized polyethoxysiloxane based mesoporous material. Structural analyses and characterizations disclose that well-defined dual single-site active centers are distributed uniformly within monodisperse mesoporous silica nanoparticles. As a bifunctional heterogeneous catalyst, this material performs the one-pot enantioselective tandem reaction of Pd-catalyzed Suzuki cross-coupling and Ru-catalyzed asymmetric transfer hydrogenation, affording various chiral biaryl alcohols with high yields and up to 99% enantioselectivity. Furthermore, the catalyst can be recovered and recycled eight times without loss of its catalytic activity, demonstrating the practicability of the preparation of optically pure biaryl alcohols in one-pot organic transformation.

• 出版日期2018-4-24
• 单位上海师范大学