论文部分内容阅读
为解决均相钯催化剂难于分离回收及循环使用问题,发展了一种廉价易行的方法合成易于原位磁分离回收的磁性纳米粒子(MNPs)负载钯催化剂Fe3O4@MOPPA-Pd.该催化剂可高效催化卤代苯的Suzuki反应及Heck反应,且对Suzuki偶联反应具有尤其高的催化活性,在温和条件下,10 mg Fe3O4@MOPPA-Pd可催化300 mmol溴苯与苯硼酸的偶联反应,联苯的分离收率达98%,转化数(TON)及转化率(TOF)分别高达77052和51368 h-1.此外,Fe3O4@MOPPA-Pd可在外加磁场存在下由反应体系中方便分离回收,循环使用4次以上催化活性无明显降低.
In order to solve the problem of difficult separation and recycling of homogeneous palladium catalysts, a cheap and feasible method for the synthesis of magnetic nanoparticle (MNPs) supported palladium catalyst Fe3O4 @ MOPPA-Pd which can be easily and magnetically separated and recovered in situ was developed. Catalyzed the Suzuki reaction and Heck reaction of halogenated benzene, and has a particularly high catalytic activity for Suzuki coupling reaction. Under mild conditions, 10 mg of Fe3O4 @ MOPPA-Pd can catalyze the coupling reaction of 300 mmol of bromobenzene with phenylboronic acid, Biphenyl separation yield of 98%, the conversion number (TON) and the conversion rate (TOF) of up to 77052 and 51368 h-1. In addition, Fe3O4 @ MOPPA-Pd in the presence of an external magnetic field can be easily separated and recovered by the reaction system , 4 times more than the use of recycled catalyst activity was not significantly reduced.