Photochemical and Magnetic Properties of Seven New Metal–Organic Frameworks Constructed by Flexible Tetrapyridines and V-Shaped Polycarboxylate Acids

Seven two- or three-dimensional (2D or 3D) coordination polymers have been synthesized by tetrakis(4-pyridyloxymethylene)methane (TPOM) with V-shaped 4,4′-oxybis(benzoicacid) (H 2 oba), 4,4′-sulfonyldibenzoic acid (H 2 sdb), 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) (H 2 hfipbb), 4,4′-dicarboxydiphenylamine (H 2 ddpa), and 4,4′-dicarboxy-ethyl diphenylamine (H 2 dedpa) in the presence of nitrates of transition metal in H 2 O/DMF systems, namely, {[Co 2 (TPOM)(oba) 2 (H 2 O) 2 ]·(H 2 O) 8 } n ( 1 ), {[Cd 2 (TPOM)(oba) 2 (H 2 O) 2 ]·(H 2 O) 4 (DMF) 1.5 } n ( 2 ), {[Ni 2 (TPOM)(oba) 2 (H 2 O) 2 ]·(H 2 O) 5 } n ( 3 ), {[Co 2 (TPOM)(hfipbb) 2 ]·(H 2 O) 3 } n ( 4 ), {[Cd 2 (TPOM)(dedpa) 2 ]·(H 2 O) 4 (DMF) 2 } n ( 5 ), {[Co 2 (TPOM)(sdb) 2 ]·(H 2 O) 3 } n ( 6 ), {[Co 2 (TPOM)(ddpa) 2 ]} n ( 7 ). Complexes 1 – 3 have similar structures, possessing 3D self-penetrated frameworks. Complex 4 is also a self-penetrated 3D framework containing meso-helix [Co(hfipbb)] n chains. Complex 5 reveals a 2-fold interlocked 2D → 2D network. For complex 6, only three pyridyl groups coordinated to Co(II) ions in one TPOM ligand, while for complex 7, only two pyridyl groups coordinated to Co(II) ions in one TPOM ligand. In addition, magnetic, fluorescence, and UV–vis properties of these complexes have been studied.