Enlarging an Isoreticular Family: 3,3′,5,5′-Tetramethyl-4,4′-bipyrazolato-Based Porous Coordination Polymers TăbăcaruAurel PettinariClaudio TimokhinIvan MarchettiFabio Carrasco-MarínFrancisco Maldonado-HódarFrancisco José GalliSimona MasciocchiNorberto 2013 The solvothermal reaction between the rigid spacer 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (H<sub>2</sub>Me<sub>4</sub>BPZ) and a number of transition metal salts promoted the formation of the coordination polymers [M­(Me<sub>4</sub>BPZ)] (M = Zn, <b>1</b>; Co, <b>2</b>; Cd, <b>3</b>; Cu, <b>4</b>). <i>Ab initio</i> X-ray powder diffraction analyses revealed the main structural aspects of the four materials. <b>1</b> and <b>2</b> are representative examples of the so-called isoreticular strategy: isostructural to [M­(BPZ)] and [M­(BDP)] (H<sub>2</sub>BPZ = 4,4′-bipyrazole; H<sub>2</sub>BDP = 1,4-bis­(1<i>H</i>-pyrazol-4-yl)­benzene), they feature three-dimensional (3-D) porous networks containing square-shaped channels. In <b>3</b>, tetrahedral Cd­(II) ions are arranged within homochiral helices reciprocally linked by radial Me<sub>4</sub>BPZ spacers, overall creating a 3-D nonporous network. Finally, the 3-D porous framework of <b>4</b> comprises square Cu<sub>4</sub> nodes linked to eight neighboring ones by the bridging spacers. Thermogravimetric analyses, coupled to variable-temperature X-ray powder diffraction, demonstrated the remarkable thermal robustness of all the materials, decomposing above 300 °C, and their stability for consecutive heating–cooling cycles. N<sub>2</sub> and CO<sub>2</sub> adsorption measurements at 77 and 273 K, respectively, were employed to probe the permanent porosity of the materials and to give a coherent picture of their textural properties including specific surface areas, micro- and mesopore volumes, as well as size distributions.