Three pillar-layered metal-organic frameworks(MOFs) based on M(HBTC)(4,4'-bipy).3DMF(M =Ni, Co, and Zn; HBTC = 1,3,5-benzenetricarboxylic acid, 4,4'-bipy = 4,4′-bipyridine) were synthesized using a solvothe...Three pillar-layered metal-organic frameworks(MOFs) based on M(HBTC)(4,4'-bipy).3DMF(M =Ni, Co, and Zn; HBTC = 1,3,5-benzenetricarboxylic acid, 4,4'-bipy = 4,4′-bipyridine) were synthesized using a solvothermal method. Zn(HBTC)(4,4'-bipy).3DMF was synthesized for the first time using both a solvothermal and microwave method, and subsequently characterized by various physicochemical methods. The structure of M(HBTC)(4,4'-bipy).3DMF consisted of honeycomb grid layers of M2+ ions and BTC units, which were further linked by the 4,4'-bipy pillars to form a three-dimensional highly porous framework. All the MOFs displayed excellent synergistic catalytic properties with alkyl ammonium halides(TBAX) in the solventless fixation of CO_2 with epoxides to produce cyclic carbonates. The catalytic activities of these MOFs followed the trend Zn Co Ni,which was explained by the acid-base bifunctional properties. The microwave-synthesized Zn(HBTC)(4,4'-bipy).3DMF material exhibited physical, chemical, and catalytic properties that were similar to those of the catalyst obtained using a conventional solvothermal synthesis. The scope of various parameters, including recyclability, was studied, and a plausible reaction mechanism was suggested.展开更多
文摘Three pillar-layered metal-organic frameworks(MOFs) based on M(HBTC)(4,4'-bipy).3DMF(M =Ni, Co, and Zn; HBTC = 1,3,5-benzenetricarboxylic acid, 4,4'-bipy = 4,4′-bipyridine) were synthesized using a solvothermal method. Zn(HBTC)(4,4'-bipy).3DMF was synthesized for the first time using both a solvothermal and microwave method, and subsequently characterized by various physicochemical methods. The structure of M(HBTC)(4,4'-bipy).3DMF consisted of honeycomb grid layers of M2+ ions and BTC units, which were further linked by the 4,4'-bipy pillars to form a three-dimensional highly porous framework. All the MOFs displayed excellent synergistic catalytic properties with alkyl ammonium halides(TBAX) in the solventless fixation of CO_2 with epoxides to produce cyclic carbonates. The catalytic activities of these MOFs followed the trend Zn Co Ni,which was explained by the acid-base bifunctional properties. The microwave-synthesized Zn(HBTC)(4,4'-bipy).3DMF material exhibited physical, chemical, and catalytic properties that were similar to those of the catalyst obtained using a conventional solvothermal synthesis. The scope of various parameters, including recyclability, was studied, and a plausible reaction mechanism was suggested.