Dalton Transactions

doi: 10.1039/D2DT90073Dpmid: N/A

doi: 10.1039/D2DT90074Bpmid: N/A

doi: 10.1039/D2DT90075Kpmid: N/A

Nie, Weixuan; McCrory, Charles C. L.

doi: 10.1039/d2dt00333cpmid: 35383803

The electrocatalytic CO2 reduction reaction (CO2RR) is a promising strategy for converting CO2 to fuels and value-added chemicals using renewable energy sources. Molecular electrocatalysts show promise for the selective conversion of CO2 to single products with catalytic activity that can be tuned through synthetic structure modifications. However, for the CO2RR by traditional molecular catalysts, beneficial decreases in overpotentials are usually correlated with detrimental decreases in catalytic activity. This correlation is sometimes referred to as a “molecular scaling relationship”. Overcoming this inverse correlation between activity and effective overpotential remains a challenge when designing new, efficient molecular catalyst systems. In this perspective, we discuss some of the concepts that give rise to the molecular scaling relationships in the CO2RR by molecular catalysts. We then provide an overview of some reported strategies from the last decade for breaking these scaling relationships. We end by discussing strategies and progress in our own research designing efficient molecular catalysts with redox-active ligands that show high activity at low effective overpotentials for the CO2RR.

Puddephatt, Richard J.

doi: 10.1039/d2dt00872fpmid: 35438702

Supramolecular chemistry and the chemistry of alkyl derivatives of the transition metals are both topics of considerable current interest, but the combination of the two fields is still underdeveloped. The challenges are, in large part, experimental in nature. For example, the self-assembly of molecules in supramolecular chemistry often relies on intermolecular hydrogen bonding, but most alkyl-transition metal bonds are cleaved by the protic groups used in hydrogen bond formation. Alkyl-platinum(iv) bonds are inert to protonolysis or attack by other electrophiles under mild conditions, and this has allowed an extensive supramolecular chemistry of organoplatinum(iv) complexes to be developed, as outlined in this perspective review. Highlights include a zeolitic structure, a polyrotaxane, a double helix, a nanotube structure and an example of spontaneous resolution to form a chiral sheet structure.

Chang, Kai-Chi; Lee, Li-Wei; Lin, Hsiu-Mei; Yen, Chih-Feng; Wang, Chih-Min; Wu, Jing-Yun

doi: 10.1039/d1dt03502apmid: 35470825

Interpenetrating porous coordination polymers (IPCPs) consist of two or more networks that are mechanically interlocked to form a coherent structure. The framework topology and the chemical composition are the two important criteria of interpenetrating networks to distinguish homo-IPCPs from hetero-IPCPs. Compared to rich homo-IPCPs, hetero-IPCPs remain rare and are formed rather unexpectedly. This Frontier article highlights hetero-IPCPs in accordance with the difference and/or identity of individual networks in terms of the framework topology and the chemical composition.

Fukuda, Kazuishi; Harada, Takuma; Iwasawa, Nobuharu; Takaya, Jun

doi: 10.1039/d2dt01222gpmid: 35481921

Bis(o-phosphinophenyl)zinc derivatives were successfully synthesized by the reaction of o-phosphinophenylboronates with dimethylzinc via boronzinc double transmetallation. The transmetallation was significantly accelerated by the presence of the ortho PR2 substituent to give diarylzinc selectively. These organozinc compounds act as isolable phenylene-tethered PZnP-pincer ligands, affording PZnP-palladium and ruthenium complexes with a -accepting Zn-metalloligand.

Stokowa-Sotys, Kamila; Kierpiec, Karolina; Wieczorek, Robert

doi: 10.1039/d2dt00328gpmid: 35319052

In many cases, human microbiota are associated with cancer progression. It was concluded that Fusobacterium nucleatum increases neoplastic changes. This bacterium is naturally present in human dental plaque. However, if it is present in the colon, it becomes a precursor of cancer. Antibiotic treatment of mice infected with F. nucleatum slowed tumor growth, which agrees with the fundamental role of bacteria in tumorigenesis. Remarkably, recent studies indicate that transition metal complexes with fragments of outer membrane proteins are able to promote reactive oxygen species (ROS) formation and are responsible for oxidative stress, which consequently leads to cell damage. Therefore, in this paper, the formation of copper(ii) complexes with fragments of adhesin YadA from F. nucleatum is characterized. Moreover, the ability of the complexes to produce ROS has been shown. Importantly, free ligands are efficient DNA-cleaving agents.

Shutava, Tatsiana; Jansen, Christian; Livanovich, Kanstantsin; Pankov, Vladimir; Janiak, Christoph

doi: 10.1039/d2dt00518bpmid: 35393994

Metalorganic framework (MOF) core particles of MIL-101(Cr), aluminum fumarate (Basolite A520), MIL-53-TDC, zirconium fumarate, and UiO-66 were modified by adsorption of thin polyelectrolyte (PE)-based shells without deterioration of their crystal structure. By applying different PEs and depositing a single layer (MOF/PE) or one to three layer-by-layer assembled bilayers (MOF/LbL), the mass percent of shell material in the composite was varied from 0.62.5% to 50%. Under a constant relative pressure of water vapor, the moisture uptake by a MOF/PE and a MOF/LbL is rather comparable with its S-shaped curvature to that of pristine MOFs. The relevant differences, such as a shift of the ascending adsorption part to lower/higher relative pressure or an increase/decrease in water uptake in selected regions, are associated with the coreshell structure and related to the morphological changes of the MOF powders. The hydrophilic surface promotes the formation of liquid menisci at the points of contact between particles and accelerates the moisture uptake and loss. A decrease in water sorption under an atmosphere with high humidity by some composites can be associated with the inhibition of liquid water condensation by the more hydrophobic shells.

Hattori, Shingo; Kondo, Mio; Sekine, Akiko; Shinozaki, Kazuteru

doi: 10.1039/d2dt00368fpmid: 35481843

We report, for the first time, a color change originating from the shift of the halide-to-ligand charge transfer (XLCT) band of the Ir(iii) bis-terpyridine complex crystal in response to the sorption/desorption of water of crystallization. Red and orange coloration reversibly takes place by heat and cool treatments, respectively. Single X-ray crystallography shows that the Ir(iii) complex possesses two waters of crystallization constructing a dimer structure, rOO = 2.911 , by hydrogen bonding. It was found that the water dimer connects to one of the iodide ions with rOI = 3.664 by hydrogen bonding and comes into contact with another iodide ion with rOI = 3.747 , suggesting that water desorption from the crystal easily changes the XLCT transition arising from the interaction between the iodide ion 5p orbital and tpy * orbital. Thermogravimetry measurement reveals the stepwise water desorption from the crystal, and powder X-ray diffraction shows the robustness of the Ir(iii) complex crystal framework during the sorption/desorption cycles. Nitrogen gas flow or presence of a polar organic solvent contributes to the red-shift of the XLCT absorption band due to the desorption of water molecules resulted by the shift of equilibrium between water molecules in the crystal and vaporized water molecules. Exposure to ammonia vapor from 25% aqueous ammonia is found not to contribute to the color change of the Ir(iii) complex crystal.