State Key Laboratory of Physical Chemistry of Solid Surfaces & Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
Nanoscale. 2019 Feb 14;11(7):3292-3299. doi: 10.1039/c8nr08734b.
Tandem catalysis (i.e., a process in which a desirable product is synthesized by a one-step process consisting of sequential reactions) has attracted intensive attention owing to its sustainable green and atom-economical characteristics. In this process, the utilization of a high-efficiency multifunctional catalyst is key. However, different functional sites integrated within the catalyst are required to be rationally designed and precisely engineered to guarantee the synergy between the catalytic reactions. Herein, a novel kind of hydrogenation-esterification tandem catalyst with metal/acid (alloy/polyoxometalates) active sites integrated within the metal-organic frameworks (MOFs) was prepared by a facile self-sacrificial template route. In this tandem catalyst, the MOF cavities served as tandem reactors, the PtNi alloy sites encapsulated within the MOF material acted as hydrogenation sites, and the solid phosphotungstic acid embedded in the MOF cavities provided esterification sites. This well-designed tandem catalyst showed outstanding activity and selectivity towards the one-step synthesis of amino-ester-type anesthetics (e.g., benzocaine) owing to the synergistic catalysis of the metal and acid sites. Clearly, this novel tandem catalyst simplifies the traditional industry process and provides a new method to rationally construct new tandem catalysts.
串联催化（即通过由连续反应组成的一步过程合成期望产物的过程）因其可持续的绿色和原子经济性特点而受到广泛关注。在该过程中，高效多功能催化剂的利用是关键。然而，需要合理设计和精确设计催化剂内的不同功能位点，以保证催化反应之间的协同作用。在此，通过简便的自牺牲模板法制备了一种新型的氢化-酯化串联催化剂，其具有金属/酸（合金/多金属氧酸盐）活性位集成在金属有机骨架（MOFs）内。在该串联催化剂中，MOF 空腔作为串联反应器，封装在 MOF 材料内的 PtNi 合金位作为氢化位，嵌入 MOF 空腔内的固体磷钨酸提供酯化位。由于金属和酸位的协同催化作用，这种精心设计的串联催化剂对氨基酯型麻醉剂（如苯佐卡因）的一步合成表现出优异的活性和选择性。显然，这种新型的串联催化剂简化了传统的工业过程，并为合理构建新型串联催化剂提供了一种新方法。
