Two new 3D (3,8)-connected metal–organic frameworks based on zinc–triazole secondary building units and benzenetricarboxylate linkers

Two new zinc–triazole–carboxylate frameworks constructed from secondary building units (SBUs), [Zn5(trz)4(btc)2(DMF)2(H2O)2]·2H2O·DMF (1) and [Zn4(trz)3(btc)2(CH3CN)(H2O)]·5H2O·(Bu4N) (2), [Htrz = 1,2,4-triazole, H3btc = 1,2,4-benzenetricarboxylate, Bu4N = tetrabutylammonium], have been synthesized by solvothermal reactions and characterized by single-crystal X-ray diffraction analyses, X-ray power diffraction, elemental analyses, infrared spectra and thermogravimetric analyses. Both compounds 1 and 2 exhibit 3D (3,8)-connected tfz-d nets with {43}2{46.618.84} topology symbol built from rod-shaped {[Zn5(trz)4]6+}n SBUs (1) and {[Zn4(trz)3]5+}n SBUs (2). In two compounds, rodlike units are connected by btc ligands via different modes. Additionally, solid state fluorescent emission spectra of two compounds show fluorescent properties at room temperature.