Metal-organic frameworks based on octafluorobiphenyl-4,4'-dicarboxylate: synthesis, crystal structure, and surface functionality

In contrast to aromatic carboxylates, the coordination polymers based on their perfluorinated analogues are not numerous. Here we present a series of six Zn(ii) coordination polymers of different dimensionalities (1D, 2D, and 3D) and porosities based on octafluorobiphenyl-4,4'-dicarboxylate (oFBPDC ) and N-containing co-ligands (ur, dabco, and bpy). These complexes are characterized by single-crystal X-ray diffraction, PXRD, FT-IR, elemental analysis, and TGA. The metal-organic frameworks [Zn (CH CONH ) (oFBPDC) ] (1) and [Zn (oFBPDC) (dabco)] (4) are shown to be porous with BET surface areas of 470 m g and 441 m g , respectively. In addition, compound 4 shows selectivity factors of 11.3, 4.9 and more than 6 for the binary gas mixtures CO /N , CO /CH and benzene/cyclohexane, respectively. The measurements for pressed powders and water droplet give water contact angles of 136° for 4 and 133° for (H bpy)[Zn (bpy)(oFBPDC) ] (5). Low water uptake indicates that both 4 and 5 belong to highly hydrophobic solids.