Cu-N/C单原子催化剂用于芳基硼酸羟基化反应

Ipso-hydroxylation of Aryl boronic Acids Catalyzed by Cu-N/C Single-Atom Catalyst

单原子催化剂中所有金属原子都能作为活性位点,故表现出极高的原子利用率和优异的催化性能。以铜-乙二胺四乙酸配合物作为前驱体,高比表面的活性炭作为载体,通过简单的吸附浸渍-高温焙烧法制备了一系列Cu-N/C催化剂。结果发现,当铜负载量为0.2 wt%时,铜以单原子的状态分散在载体上,得到0.2 wt%Cu-N/C(1∶1)单原子催化剂。该催化剂在芳基硼酸羟基化制苯酚的反应中具有优异的活性,可以直接用氧气作为氧化剂,反应效率达到3250 mmol_(产物)/g_(Cu),高于铜纳米颗粒催化剂6倍。此外,该单原子催化剂稳定性较好,并且该反应对各种带有吸电子或供电子基团的芳基硼酸都具有良好的底物适用性。

Single-atom catalysts can improve the catalytic performance by maximizing the atomic efficiency of active metal species,thus exhibiting high catalytic performance.A series of Cu-N/C catalysts were prepared by impregnating active carbon material with Cu-EDTA complex precursor and the subsequent calcination.The synthesized 0.2 wt%Cu-N/C(1∶1)single-atom catalyst carries out the ipso-hydroxylation of phenylboronic acid to produce phenol under O_(2)atmosphere with a catalytic efficiency of 3250 mmol_(product)/g_(Cu),which was 6 times higher than that of Cu nanoparticle catalyst.In addition,the single-atom catalyst has good stability,and the reaction has good substrate applicability to various aryl boronic acids with electron withdrawing/donating groups.