Metalorganic frameworks based on the 1,4-bis(5-tetrazolyl) benzene ligand: The Ag and Cu derivatives

Abstract

The recently proposed high-yield synthesis of the 1,4-bis(5-tetrazolyl)benzene ligand (H2btb) allowed the preparation of three new metal organic frameworks, namely Ag2(btb), 1, Cu2(btb), 2, and Cu2(OH)2(btb), 3. These polycrystalline materials were fully characterised by spectroscopic, gas adsorption, thermal and diffraction methods, the latter revealing rather dense frameworks for 1 and 3. Despite many different synthetic approaches, 2 invariably gave a poorly resolved, but highly reproducible, powder diffraction trace, hampering a complete structural characterisation. Magnetic measurements performed on 3 showed that it behaves as an antiferromagnetic material, the r.t. magnetic moment per Cu atom being only 1.24 BM. The reactivity of 1 was proved in excess of triphenylphosphine (PPh3), allowing the isolation of the dinuclear species 4, [(PPh3)3Ag]2(btb). An additional species 5, formulated as [(PPh3)Ag]2(btb), could be selectively isolated on varying the reaction conditions; at variance, pyrazine, in solution or in molten form, did not react with 1

An iron (II) complex containing well-resolved 1D water chain and 1D chain of copper (II) complex with bis(tetrazoly)amine: Syntheses, crystal structures and properties

“…The first weight-loss step (found 15.8%, calcd 16.4%) corresponds to the loss of water molecules. The initial and final DTs are around 234 and 350°C, which is near to those found in another tetrazole complexes Cu 2 (btb) (250-350°C) [33].…”

Fluorous Metal–Organic Frameworks and Nonporous Coordination Polymers as Low‐κ Dielectrics

“…FN‐PCP‐1, isostructural to [Ag 2 (BTB)], is built up of tetrahedral AgN 4 nodes ( Figure a) and µ 8 ‐FBTB 2− spacers. Overall, it is a (4,8)‐connected nonporous and dense ( d c = 2.94 kg L −1 ) network, with a rather complex 3D architecture (Figure b; Figure S1, Supporting Information).…”

“…Synthesis of [Ag 2 (BTB)] : [Ag 2 (BTB)] was obtained in the form of brownish microcrystalline powders by following a previously reported procedure . IR (cm −1 ): 1377 (m), 1278 (m), 1219 (vw), 1157 (m), 1109 (w), 1083 (w), 1039 (w), 1005 (w), 845 (s), 741 (s).…”

“…After fast preliminary acquisitions in the 2θ range 3–35° for qualitative analysis, diffraction data for structure refinements were collected at room temperature, in the 2θ range 5–105°, with steps of 0.02° and a total scan time of ≈12 h, on the Bruker AXS D8 Advance diffractometer described above. Comparison between the PXRD patterns of FMOF‐3 versus [Cu(BTB)(DMF)] and FN‐PCP‐1 versus [Ag 2 (BTB)] suggested that the two fluorinated compounds are isostructural to the nonfluorinated counterparts. Hence, refinement of the crystal structures of FMOF‐3 and FN‐PCP‐1 were carried out, by applying the Rietveld method as implemented in TOPAS‐R, starting from the structural models of [Cu(BTB)(DMF)] and [Ag 2 (BTB)], respectively.…”

“…To widen the scope of this investigation, we also focused the attention on a novel FMOF and a novel FN‐PCP. We have synthesized for the first time the fluorinated ligand 1,4‐bis(1‐ H ‐tetrazol‐5‐yl)tetrafluorobenzene (H 2 FBTB, Scheme ) and employed it to build up the Cu(II)‐based (FMOF‐3) and Ag(I)‐based (FN‐PCP‐1) derivatives isostructural to the already known MOF [Cu(BTB)(DMF)] and N‐PCP [Ag 2 (BTB)] (H 2 BTB = 1,4‐bis(1‐ H ‐tetrazol‐5‐yl)benzene), respectively. FMOF‐3 represents a more economical choice of the metal center (copper vs silver), as already done by Miljanić and co‐workers with extensively fluorinated MOFs (MOFFs), whereas FN‐PCP‐1 provides a platform for comparison upon varying the metal center with the same ligand.…”