Syntheses of new topology BTTB-based metal–organic frameworks in CH<sub>3</sub>CN/H<sub>2</sub>O mixed solvents

<p>Three complexes, [Zn<sub>2</sub>(BTTB)](H<sub>2</sub>O)<sub>5</sub> [BTTB = 4,4′,4″,4′″-benzene-1,2,4,5-tetrayltetrabenzoate, also named 1,2,4,5-tetrakis(carboxyphenyl) benzene] (<b>1</b>), [Cd<sub>2</sub>(BTTB)(H<sub>2</sub>O)<sub>5</sub>](H<sub>2</sub>O)<sub>3</sub> (<b>2</b>) and [Mn<sub>2</sub>(BTTB)(H<sub>2</sub>O)<sub>5</sub>](H<sub>2</sub>O)<sub>2</sub> (<b>3</b>), have been synthesized under hydrothermal conditions in CH<sub>3</sub>CN/H<sub>2</sub>O. Structural analyses revealed that <b>1</b> has new topologies, i.e. <b><i>nnu1</i></b> (<b><i>nnu</i></b> stands for Nanjing Normal University) or <b><i>nnu2</i></b> depending on the different simplification schemes. Compounds <b>2</b> and <b>3</b> are isostructural and have a <b><i>scu</i></b> (square planar and cubical vertices) topology, which have not been reported for BTTB-based metal–organic frameworks. Thermal stability of <b>1</b>–<b>3</b>, hydrogen adsorption/desorption properties of <b>2</b> and <b>3</b>, and luminescent properties of <b>1</b> and <b>2</b> were investigated. Compounds <b>1</b>–<b>3</b> are stable in air.</p>