Highly Selective Sorption of Small Hydrocarbons and Photocatalytic Properties of Three Metal–Organic Frameworks Based on Tris(4-(1<i>H</i>‑imidazol-1-yl)phenyl)amine Ligand

By employing a tris­(4-(1H-imidazol-1-yl)­phenyl)­amine (Tipa) ligand, three new metal–organic frameworks, [Zn2(Tipa)­(4,4′-bpdc)1.5(H2O)­(NO3)]·2­(DMF)·H2O (1; 4,4′-bpdc = 4,4′-biphenyldicarboxylate, DMF = N,N-dimenthylformamide), [Cd­(Tipa)­Cl2]·2­(DMF)·H2O (2), and [Co­(Tipa)­Cl2(H2O)]·DMF·H2O (3), have been synthesized solvothermally. Compound 1 features a three-dimensional (3D) pillared-layer structure with low band gap and interesting photocatalytic properties. Compound 2 is a 2-fold interpenetrating (3,6)-connected porous framework, and it shows highly selective adsorption of C2H2, CO2, and C2H4 over CH4. Compound 3 with honeycomb-like layers exhibits unusual 2D + 2D→ 3D polycatenation (2D = two-dimensional). The luminescent properties for these compounds were also investigated.