Construction of first anion-assisted helix inside a helix network

Solid-State Landscape of 4,4′-Azobis(3,5-dimethyl-1H-pyrazole) with the Isolation of Conformer-Dependent Polymorphs

“…AB-stacking of the hcb sheets, similar to the case of H 2 azbpz- II , takes place also in H 2 bpz and H 2 bpzb (Chart , Figures S26 and S27, Supporting Information). , The polymorphs of hinged H 2 Me 4 mpz features corrugated hcb sheets arranged in an AB-stacking for the α-form and in an AA-stacking for the β-form …”

“… a Compound names with CCDC-Refcodes and assigned supramolecular topologies in parentheses: H 2 bpz = 4,4′-bis-1 H -pyrazole (UDAYIH, hcb ), H 2 Me 4 bpz = 4,4′-bis­(3,5-dimethyl-1 H -pyrazole) (UDAYUT, ths ; UDAYUT01, bto ; UDAYUT02, srs ), , H 2 mbpz = 4,4′-methylenebis­(1 H -pyrazole) (HEPHUF, hcb ), H 2 Me 4 mbpz = 4,4′-methylenebis­(3,5-dimethyl-1 H -pyrazole) (HEPJAN01, hcb ; HEPJAN02, hcb ), , H 2 bpzb = 1,4-bis­(1 H -pyrazol-4-yl)­benzene (VONVEA, hcb ), 3,3′-azobis­(1 H -pyrazole) (no single-crystal data available) and H 2 azbpz = 4,4′-azobis­(3,5-dimethyl-1 H -pyrazole) (presented in this work). Presentation of the crystal packings of these bispyrazoles can be found in the Supporting Information in Figures S27–S28. …”

Coordination sphere hydrogen bonding as a structural element in metal–organic Frameworks

“…The conformational flexibility of the V-shaped H 2 L3 ligand can give rise to intriguing structural features, 54a,b and is often observed imparting a helical character onto the resulting networks. The propensity for H 2 L3 to form helical assemblies is also observed in the salts of the compound itself, 55 and has also been exploited in the synthesis of discrete helical complexes from a 2-pyridyl appended L3 derivative. 56 However, given the difficulties with preparing permanently porous frameworks contain-ing flexible backbones, and the relatively large steric bulk of the H 2 L3 ligand, to date no permanently porous frameworks containing this ligand in its protonated form have been reported.…”

Crystal structure of an organic–inorganic supramolecular salt based on a 4,4′-methylenebis(3,5-dimethyl-1H-pyrazol-2-ium) cation and a β-octamolybdate anion

“…A search in the literature and in the Cambridge Structural Database (CSD; Allen, 2002;Groom & Allen, 2014) reveals, for example, that H 2 mbdpz has been used as an effective bending spacer to construct a large number of metal-organic frameworks (MOFs) or coordination polymers with various remarkable topologies based on a rather diverse range of d-block metals (Goswami et al, 2013;Mondal et al, 2008;Timokhin et al, 2015). H 2 mbdpz and its derivatives have also been used to prepare a range of supramolecular networks based on either neutral organic molecules or in the formation of salts with a wide range of anions (since, typically, the two pyrazole moieties appear protonated) (Basu et al, 2009;Basu & Mondal, 2010;Hazra et al, 2010). Most of these structural reports available in the literature either use H 2 mbdpz purchased from commercial sources or the authors prepare the molecule using published procedures.…”