Solvent Dependent Structures of Hydrogen-Bonded Organic Frameworks of 2,6-Diaminopurine

Three solvent dependent structures of 2,6-diaminopurine in <i>N</i>,<i>N</i>′-dimethylforamide (<b>DAP-1-DMF</b>), water (<b>DAP-2-H</b>_<b>2</b><b>O</b>), and methoxybenzene (<b>DAP-3-CH</b>_<b>3</b><b>OC</b>_<b>6</b><b>H</b>_<b>5</b>) have been structurally characterized. They exhibit different structures because of the different involvement of solvent molecules in the hydrogen bonded frameworks. The DAP molecules tend to be self-assembled with other DAP molecules through hydrogen bonding interactions. DAP has very similar hydrogen bonding interaction patterns to the established DAT group (2,4-diaminotriazinyl), underlying the potential of this new unit for the construction of porous hydrogen bonded organic frameworks

A Fluorinated Metal–Organic Framework for High Methane Storage at Room Temperature

A fluorinated metal–organic framework NOTT-108 with single pure-phase has been synthesized for the first time, which has enabled us to examine the effect of the substituted fluorine atoms on the methane storage. The activated NOTT-108a shows a permanent porosity comparable to its isoreticular NOTT-101a but exhibits a higher volumetric methane storage capacity of 247 cm³ (STP) cm^–3 and a working capacity of 186 cm³ (STP) cm^–3 (at 298 K and 65 bar) than 237 cm³ (STP) cm^–3 and 181 cm³ (STP) cm^–3 of NOTT-101a, attributed to the higher polarity/dipole moment of C–F bonds compared to that of C–H bonds for the enhanced electrostatic interaction with methane molecules

Solvent Dependent Structures of Melamine: Porous or Nonporous?

Two hydrogen-bonded organic frameworks (HOFs) of the melamine (MA), <b>MA-1-H₂O</b> and <b>MA-2-DMF</b>, have been crystallized in H₂O and DMF (<i>N</i>,<i>N</i>-Dimethylformamide), respectively. Structurally, <b>MA-1-H</b>_<b>2</b><b>O</b> and <b>MA-2-DMF</b> are condensed and porous, respectively. The porous <b>MA-2-DMF</b> sustains the porous feature under the solvent exchange by acetone, dichloromethane (CH₂Cl₂), and toluene, while it transforms into the condensed one under methanol (MeOH) and ethanol (EtOH). Furthermore, <b>MA-2-DMF</b> and <b>MA-2-Toluene</b> can undergo reversible single crystal–single crystal transformation with retention of the porous hydrogen-bonded organic frameworks

A Microporous Porphyrin-Based Hydrogen-Bonded Organic Framework for Gas Separation

A hydrogen-bonded organic framework (HOF), HOF-7, based on a zinc porphyrin-based building block (ZnTDPP) with diaminotriazine moieties has been successfully constructed and structurally characterized (ZnTDPP = 5,10,15,20-tetrakis­(4-(2,4-diamino­triazinyl)­phenyl)­porphyrinato zinc). Single-crystal X-ray diffraction analysis reveals that HOF-7 is built by the 2D layered subunits connected by the intermolecular hydrogen-bonding and π–π interaction, exhibiting two kinds of micropores with sizes of 3.2 × 4.7 Ų and 4.2 × 6.7 Ų, respectively. This HOF exhibits permanent porosities as demonstrated in the CO₂ sorption and selective adsorption of CO₂ over N₂

A Microporous Porphyrin-Based Hydrogen-Bonded Organic Framework for Gas Separation

A hydrogen-bonded organic framework (HOF), HOF-7, based on a zinc porphyrin-based building block (ZnTDPP) with diaminotriazine moieties has been successfully constructed and structurally characterized (ZnTDPP = 5,10,15,20-tetrakis­(4-(2,4-diamino­triazinyl)­phenyl)­porphyrinato zinc). Single-crystal X-ray diffraction analysis reveals that HOF-7 is built by the 2D layered subunits connected by the intermolecular hydrogen-bonding and π–π interaction, exhibiting two kinds of micropores with sizes of 3.2 × 4.7 Ų and 4.2 × 6.7 Ų, respectively. This HOF exhibits permanent porosities as demonstrated in the CO₂ sorption and selective adsorption of CO₂ over N₂