The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Carbohydr Polym. 2017 Nov 1;175:113-121. doi: 10.1016/j.carbpol.2017.07.052. Epub 2017 Jul 19.
To maintain stability and activity in Heck-coupling reaction, a novel composite carrier with controllable uniform size, high complex ability and mechanical intensity was fabricated in microchannel using natural N-doped biomolecule chitosan and silica as ingredients. Post carbonization increased its thermal stability and supported Pd@C/silica catalysts can be acquired after Pd loading. Only 2mg supported Pd@C/silica catalysts (0.44μmol) can achieve high yield (>95%) in a typical Heck-coupling reaction and maintained activity even after 8 times of recycling. This type of novel porous microspheres carrier can cut down the usage of noble Pd by avoiding the leaching as well as aggregation of Pd nanoparticles, and could be widely applied in similar chemical reactions.
为了在 Heck 偶联反应中保持稳定性和活性，使用天然掺杂氮的生物分子壳聚糖和二氧化硅作为原料，在微通道中制造了一种具有可控均匀尺寸、高络合能力和机械强度的新型复合载体。碳化后提高了其热稳定性，负载钯后可以得到 Pd@C/二氧化硅催化剂。在典型的 Heck 偶联反应中，仅使用 2mg 负载的 Pd@C/二氧化硅催化剂（0.44μmol）即可获得高产率（>95%），并且经过 8 次循环后仍保持活性。这种新型多孔微球载体可以通过避免钯纳米粒子的浸出和聚集来减少贵金属钯的使用，并可以广泛应用于类似的化学反应中。
