Combination of POMs and deliberately designed macrocations: a rational approach for synthesis of POM-pillared metal-organic framework

摘要

Two POM-pillared 3D porous compounds, [(CuCuII)-Cu-I(Cu(II)fcz)(2)(H2O)(5)((PMo10Mo2O40)-Mo-VI-O-V)]center dot 6H(2)O (1) and [Cu-2(I)(Cu(II)fcz)(2)(H2O)(2)((PMo8V3V3O42)-V-VI-V-V-O-IV)]center dot 6H(2)O (2) (Hfcz = fluconazole, (1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]benzyl alcohol) have been constructed based on different polyanions, (Cufcz)(2)(2+) macrocations and copper cations by the hydrothermal method. The (Cufcz)(2)(2+) macrocations link Cu cations to generate a 2D wavelike cationic sheet. Then the POM anions act as pillars to the cationic sheet to form different POM-pillared 3D frameworks. In compound 1, the polyanion exhibits a rare coordination mode and acts as a penta-dentate ligand, which acts as to pillars to the cationic sheet to form an unprecedented 3D (3,4,5,6)-connected open framework with (3.6.7)(3(2).6.7(3))(3(3).4.6(2).7(3).8)(3(4).4(2).6(2).7(6).8)(3(2).6( 2).7(6).8(4).10) topology. In compound 2, polyanions covalently link cationic sheets to extend to an unusual 3D (3,4,6)-connected framework with the (5(2).6)(5(2).6(2).7.9)(5(4).6(4).7(4).9(3)) topology. To the best of our knowledge, it is the first time that POM-pillared 3D metal-organic frameworks have been realized by combining POMs with deliberately designed macrocations and transition-metal ions, using a rational approach for synthesis of POM-based open metal-organic frameworks. In addition, the electrochemical behaviors of compounds 1 and 2 have been investigated.