摘要
The palladium(Pd)-catalyzed Suzuki reaction is widely applied in the pharmaceutical industry,where constructing highly active and low-cost Pd sites are impendent.Here,we report the fabrication of a heterogeneous Pd/Tio2 catalyst via engineering of an electronic structure of a single Pd_(1)atom on monolayered Ti_(0.87)O_(2)nanosheet(Pd_(1)-Ti_(0.87)O_(2)).This catalyst motivated the kinetically sluggish C-Br cleavage,thus boosting the Suzuki reaction at room temperature.Pd_(1)-Ti_(0.87)O_(2)exhibited an outstanding activity with turnover frequency(TOF)of 11,110 h-1,exceeding that of PdCl_(2)and Pd(OAc)_(2)catalysts by a factor of>200.Various in situ techniques were employed to investigate the C-Br activation process,which showed that Pd_(1)kinetic-feasibly dissociated the chemisorbed bromobenzene,especially the C-Br bond cleavage.Theoretical calculations further revealed that the improved activity is ascribed to the optimized charge state of Pd_(1)within the Pd_(1)O4 realm via charge transfer.
基金
This study was supported financially by the National Natural Science Foundation of China(grant nos.91961125,21905019,and 21903001)
the Fundamental Research Funds for the Central Universities(grant nos.2018JBZ107 and 2019RC035)
the Ministry of Science and Technology of China(grant no.2018YFE0124600)
the Chemistry and Chemical Engineering Guangdong Laboratory(grant no.1932004)
the Natural Science Foundation of Anhui Province(grant no.1908085QB58)。
