Highly reactive and reusable heterogeneous activated carbons-based palladium catalysts for Suzuki-Miyaura reaction

Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium cat-alyst based on activated carbons (AC) was systematically investigated in this work. Two different reaction modes (batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode. This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heteroge-neous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and dura-bility in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports.& COPY; 2023 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

This study systematically investigated the application of a heterogeneous palladium catalyst based on activated carbons (AC) in the Suzuki-Miyaura reaction of aryl halides with phenylboronic acid. The variations of reaction processing were studied using batch and continuous-flow procedures. The heterogeneous catalysts exhibited excellent reactivity and recyclability in batch mode, but significant dehalogenation and Pd leaching were observed in continuous-flow mode, leading to a decline in reaction selectivity and durability of the catalysts. Additionally, the reactivity and durability of the heterogeneous Pd catalysts with thiol-and amino-modified AC supports differed in batch and continuous-flow mode due to the difference in interaction between Pd species and AC supports.