A Proton Conductive Porous Framework of an 18-Crown-6-Ether Derivative Networked by Rigid Hydrogen Bonding Modules

A rigid hydrogen-bonded organic framework (HOF) was constructed from a C3-symmetric hexatopic carboxylic acid with a hydrophilic 18-crown-6-ether (18C6) component. Despite the flexible macrocyclic structure with many conformations, the derivative with three 4,4’-dicarboxy-o-terphenyl moieties in the periphery yielded a rigid layered porous framework through directional intermolecular hydrogen bonding. Interestingly, the HOF possesses 1D channels with bottleneck composed of 18C6 rings. The HOF shows proton conductivity (1.12×10−7 S cm−1) through Grotthuss mechanism (Ea=0.27 eV) under 98 %RH. The present unique water channel structure provides an inspiration to create molecular porous materials.This is the accepted version of the following article:Chen X., Huang R.K., Takahashi K., et al. A Proton Conductive Porous Framework of an 18-Crown-6-Ether Derivative Networked by Rigid Hydrogen Bonding Modules. Angewandte Chemie - International Edition 61, e202211686 (2022), which has been published in final form at https://doi.org/10.1002/anie.202211686. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html

Orthogonality of Jahn-Teller axes in a dinuclear Cu(II) complex bridged by one F- anion

The dinuclear Cu(II) complex bridged by a single F- anion has orthogonal Jahn-Teller axes, which induce a ferromagnetic interaction between the intramolecular Cu(II) ions

Synthesis and Crystal Structure of a One-dimensional Cu(II) Coordination Polymer Bridged by Inorganic CH3SO3- Anions Using Werner-type Cu(II) Complexes as Building Blocks

The reaction of [Cu(PF6)2(py)4] (py = pyridine) with [Cu(CH3SO3)2(py)4], both of which are Werner-type Cu(II) complexes, in a MeOH solution led to the formation of a one-dimensional framework composed of [-{Cu(1)2(MeO)2}-Cu(2)-Cu(3)-Cu(3)-Cu(2)-] repeating units bridged by inorganic CH3SO3- anions

Influence of carbohydrate polymer shaping on organic dye adsorption by a metal-organic framework in water

A number of studies have been conducted to develop new metal-organic frameworks (MOFs) as adsorbents for the removal of contaminants from polluted water. However, few reports exist describing detailed and thorough examinations of the effects of shaping on the adsorption properties of MOFs. In this study, a thorough analysis and comparison was conducted of the Orange II and Rhodamine B dye adsorption properties of unshaped MIL-100(Fe) (MIL) particles and alginate polymer-shaped MIL beads (MIL-alg). The adsorption affinities of Orange II and Rhodamine B for unshaped MIL were observed to be higher than those for shaped MIL-alg because partial coating of the surface of MIL particles by alginate polymer weakens adsorption forces. Kinetic analysis using a two-compartment model indicates that the contribution of the slow step in the mechanistic pathway for adsorption is more pronounced in MIL-alg compared to MIL because slow dye diffusion takes place in the alginate polymer. We believe that these fundamental findings will have a beneficial impact on approaches to design shaped MOFs that display improved dye removal performance

Multifunctional sensing ability of a new Pt/Zn-based luminescent coordination polymer

We synthesized a new Pt/Zn-based coordination polymer, {Zn[Pt(CN)2(5,5'-dcbpy)]・4H2O}n, (5,5'-H2dcbpy = 5,5'-dicarboxy-2,2'-bipyridine), which exhibits reversible colour changes in response to temperature change or exposure to chemical vapours and liquids. Such chromic behaviour shows promise for sensing not only changes in temperature but also for detecting chemical solvents and vapours. The single crystal X-ray structure indicates that one-dimensional coordination polymeric chains formed by an alternating arrangement of [Zn(H2O)3]2+ and [Pt(CN)2(5,5'-dcbpy)]2- stacked to produce moderate metallophilic interactions between the Pt(II) ions. Thermogravimetric analysis and water vapour adsorption measurements show that both the crystal water and water coordinated to Zn(II) ions can be removed and re-adsorbed reversibly by heating or under vacuum. Emission spectra at various temperatures and/or in the presence of vapours or liquids reveal that the complex exhibits thermochromic and solvatochromic-like behaviours, with the emission band shifting between 616 and 671 nm. IR spectroscopy and powder X-ray diffraction measurements suggest that this multichromic behaviour is a result of the cooperative phenomena of water adsorption/desorption around the Zn(II) ions and the modification of the metallophilic interaction

Electron transport in a gold nanoparticle assembly structure stabilized by a physisorbed porphyrin derivative

Gold nanoparticles stabilized by meso-5,10,15,20-tetrakis(2-thienyl)porphyrin (2T) via physisorption (2T-AuNP) were synthesized, and the electronic transport of assemblies of these films was studied. The adsorption mechanism of 2T on gold nanoparticles was examined using UV-vis-NIR, IR, Raman, and H-1-NMR spectroscopy, which showed no evidence of any covalent bonding between 2T and the gold nanoparticles. In temperature-dependent resistivity measurements, a crossover from thermally assisted hopping to Efros-Shklovskii-type variable-range hopping (ES-VRH) was observed around 50 K on decreasing the temperature. At higher temperatures, the 2T-AuNP assembly structure followed an Arrhenius plot (E-A=15 meV) with ohmic I-V characteristics at each measurement point. On the other hand, the activation energy at lower temperatures decreased nonlinearly in a T-1 plot, and the logarithm of the resistance obeyed a T-1/2 law, corresponding to an ES-VRH mechanism, which is predicted for disordered materials as a variable-range hopping mechanism influenced by strong Coulomb interactions. ES-VRH behavior has been observed previously in saturated molecule/gold nanoparticle assemblies and was confirmed in our 2T-AuNP assembly. Electronically active conjugated molecules were successfully incorporated between the nanoparticles, keeping the electronic structure of the gold nanoparticle and 2T moieties isolated from each other

Synthesis, Crystal Structure, and Adsorption Properties of Werner-type Cu(II) Complex [Cu(CF3SO3)2(4-methylpyridine)4]

A Werner-type Cu(II) complex, α-[Cu(CF3SO3)2(4-mepy)4] (α-PAC-1-CF3SO3, PAC: porous assembly of coordination complex and 4-mepy: 4-methylpyridine), was synthesized, crystallographically characterized, and its adsorption properties were compared with those of the derivative α-[Cu(PF6)2(4-mepy)4] (α-PAC-1-PF6)