Fabrication of (4,10) and (4,12)-Connected Multifunctional Zirconium Metal-Organic Frameworks for the Targeted Adsorption of a Guest Molecule

Following the principle of a topology guide, a zirconium MOF (PCN-207) based on the H(4)TPTA ligand (tetramethyl(4,4',4 '',4"'-(pyrazine-2,3,5,6-tetrayl))-tetrabenzoic acid) with C-2 symmetry and an 8-connected Zr-6(mu(3)-OH)(8)(OH)(8)](8+) cluster with D-4h symmetry has been synthesized. PCN-206 can also be obtained by modulating the benzoic acid usage to change the flexibility of the H(4)TPTA ligand. The unique positions of 8-connected Zr-6 clusters in the flu and scu networks and the flexibility of the tetratopic primary linker enable the precise insertion of fumarate (FA), 1,4-benzenedicarboxylic acid (H2BDC), and even 2,6-naphthalenedicarboxylic acid (H2NDC) in a one-pot reaction. Auxiliary linkers are used to generate new MOF structures or topologies or to split the pore spaces, which may significantly change the porosity and chemical and physical properties of scaffold MOFs. The results provide a successful strategy for the rational design of multicomponent Zr-MOFs. Because of differences in composition and configuration between structures, PCN-207 shows the highest separation capability of light hydrocarbons; moreover, PCN-206 exhibits the highest adsorption capacity of 2,4-D and DCF among MOFs at present.