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Sodium zirconate (sodium zirconium oxide; Na2ZrO3) is a widely investigated carbon dioxide (CO2) sorbent. Since it was first discussed in the 1960s, Na2ZrO3 has been reported to adopt monoclinic, hexagonal, and cubic structures, and it is widely believed that the CO2 capture performance of Na2ZrO3 is related to its crystal structure. Researchers have relied on the differences in the relative intensities of two peaks (2 ∼16.2° and 38.7°) in the powder X-ray diffraction (PXRD) pattern to determine the phase of this compound. However, to date, a defined crystal structure of hexagonal Na2ZrO3 has remained elusive. Our findings show that the current literature discussion on the structure of Na2ZrO3 is misleading. With the use of 3D electron diffraction (3D ED), and PXRD, we prove that hexagonal Na2ZrO3 does not exist. The so-called hexagonal Na2ZrO3 is actually Na2ZrO3 with three different types of disorder. Furthermore, the two PXRD peaks (2 ∼16.2° and 38.7°) cannot be used to distinguish the different phases of Na2ZrO3, as the change in the PXRD pattern is related to the extent of structure disorder. Finally, we also show that the CO2 uptake properties of Na2ZrO3 are not related to the differences in crystal structures, but rather to the Na+ site occupancy differences in different Na2ZrO3 samples. In order to further develop applications of Na2ZrO3, as well as other mixed-metal oxides, their structures, and the existence of any disorder, need be understood using the methods shown in this study. [ABSTRACT FROM AUTHOR]

Maximizing products of high value and minimizing incineration of side-streams is key to realize future biorefineries. In current textile production from forestry, hemicellulose is removed by prehydrolysis before delignification. The resulting prehydrolysis liquor is incinerated in the recovery boiler at low efficiency. This additional burden on the limiting recovery boiler reduces the pulp production. In this study, we demonstrate that prehydrolysis liquor can be upgraded, in 5 steps, to yield aviation fuels. Prehydrolysis liquors were dehydrated to furfural by zeolite catalysis. Furfural was selectively reduced to furfuryl alcohol by Au@NC. Rhenium-catalysed Achmatowicz rearrangement gave a C5 intermediate susceptible to self [2 + 2] cycloaddition to give the C10 oxygenated precursor. By using a combination of Ru/C and zeolites, full hydrodeoxygenation was achieved. The overall transformation from furfural to hydrocarbons resulted in a 48% carbon yield. The resulting hydrocarbons, containing an anticipated strained four-membered ring, are preferred aviation fuel components. This is an important step to show that aviation fuels can be produced sustainably from existing industrial side-streams. A comparative life cycle assessment was applied to evaluate the environmental impact of the proposed valorization approach, demonstrating benefits in the climate change impact category when implementing this technology in a pulp mill compared to the incineration of pre-hydrolysis liquor scenario. [ABSTRACT FROM AUTHOR]

A direct catalytic stereoselective synthesis of C4' functionalized furanoside and nucleoside derivatives with a tetrasubstituted stereocenter is disclosed. The amine‐catalyzed stereoselective α‐aminomethylation reactions on furanoside‐derived aldehyde derivatives gave the corresponding C4' functionalized D‐ or L‐ribose derivatives in good to excellent yields (67−94%) with up to >20:1 dr. [ABSTRACT FROM AUTHOR]

The transition-metal free S-vinylation of thiophenols by vinylbenziodoxolones (VBX) constituted an important step forward in hypervalent iodine-mediated vinylations, highlighting the difference to vinyliodonium salts and that the reaction outcome was influenced by the substitution pattern of the benziodoxolone core. In this study, we report several new classes of hypervalent iodine vinylation reagents; vinylbenziodazolones, vinylbenziodoxolonimine and vinyliodoxathiole dioxides. Their synthesis, structural and electronic properties are described and correlated to the S-vinylation outcome, shedding light on some interesting facets of these reagents. [ABSTRACT FROM AUTHOR]

Functionalized triose‐, furanose and chromane‐derivatives were synthesized by the titled reactions. The sugar‐assisted kinetic resolution/C−C bond‐forming cascade processes generate a functionalized sugar derivative with a quaternary stereocenter in a highly enantioselective fashion (up to >99 % ee) by using a simple combination of metal and chiral amine co‐catalysts. Notably, the interplay between the chiral sugar substrate and the chiral amino acid derivative allowed for the construction of a functionalized sugar product with high enantioselectivity (up to 99 %) also when using a combination of racemic amine catalyst (0 % ee) and metal catalyst. [ABSTRACT FROM AUTHOR]

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The solution chemistry of aluminum is highly complex and various polyoxocations are known. Here we report on the facile synthesis of a cationic Al24 cluster that forms porous salts of composition [Al24(OH)56(CH3COO)12]X4, denoted CAU‐55‐X, with X=Cl−, Br−, I−, HSO4−. Three‐dimensional electron diffraction was employed to determine the crystal structures. Various robust and mild synthesis routes for the chloride salt [Al24(OH)56(CH3COO)12]Cl4 in water were established resulting in high yields (>95 %, 215 g per batch) within minutes. Specific surface areas and H2O capacities with maximum values of up to 930 m2 g−1 and 430 mg g−1 are observed. The particle size of CAU‐55‐X can be tuned between 140 nm and 1250 nm, permitting its synthesis as stable dispersions or as highly crystalline powders. The positive surface charge of the particles, allow fast and effective adsorption of anionic dye molecules and adsorption of poly‐ and perfluoroalkyl substances (PFAS). [ABSTRACT FROM AUTHOR]

Encapsulating and protecting dopamine from oxidation is a difficult challenge. We propose to use SU-101 BioMOF as a dopamine host, where we study different adsorption scenarios by a robust computational approach. Our results show that dopamine encapsulation is feasible with the formation of non-covalent interactions within the SU-101 pores. These computational results have been corroborated experimentally. [ABSTRACT FROM AUTHOR]

Multifunctional, biobased materials processed by means of additive manufacturing technology can be highly applicable within the water treatment industry. This work summarizes a scalable and sustainable method of anchoring a green metal–organic framework (MOF) SU-101 onto the surface of 3D printed, biobased matrices built of polylactic acid (PLA)-based composites reinforced with TEMPO-oxidized cellulose nanofibers (TCNFs). The two tested anchoring methods were hydrolysis via either concentrated hydrochloric acid treatment or via a photooxidation reaction using UV–ozone treatment. Stable deposition of SU-101 distributed homogenously over the filter surface was achieved and confirmed by FT-IR, XPS and SEM measurements. The obtained 3D printed and functionalized MOF@PLA and MOF@TCNF/PLA (aka MOF@Cell) filters exhibit high efficiency in removing heavy metal ions from mine effluent and methylene blue from contaminated water, as demonstrated through batch adsorption experiments. In addition to their potential for removal of contaminants from water, the MOF@Cell filters also exhibit excellent mechanical properties with a Young's modulus value of about 1200 MPa, demonstrating their potential for use in practical water treatment applications. The MOF@Cell filters were able to maintain their structural integrity and filtration performance even after multiple cycles of use and regeneration. This study highlights the potential of multifunctional, biobased materials processed by additive manufacturing technology as a cost-effective alternative to traditional water treatment methods. The MOF@Cell filters presented in this study demonstrate high efficiency, durability, and reusability, making them promising candidates for practical applications in the modern water treatment industry. [ABSTRACT FROM AUTHOR]

We report an efficient radical‐mediated C−C coupling through photoredox‐catalyzed reactions of 4‐alkyl‐dihydropyridines (DHPs) and vinylbenziodoxol(on)es (VBX, VBO). This transition‐metal‐free and mild photocatalytic method has excellent functional group tolerance and affords vinylated products in good yields, with complete retention of the alkene configuration. The utility of the methodology is demonstrated by the diastereoselective synthesis of C‐vinyl glycosides. Preliminary mechanistic studies suggest that the C−C bond formation is stereospecific and proceeds through a concerted radical coupling transition state. [ABSTRACT FROM AUTHOR]

We report an efficient radical‐mediated C−C coupling through photoredox‐catalyzed reactions of 4‐alkyl‐dihydropyridines (DHPs) and vinylbenziodoxol(on)es (VBX, VBO). This transition‐metal‐free and mild photocatalytic method has excellent functional group tolerance and affords vinylated products in good yields, with complete retention of the alkene configuration. The utility of the methodology is demonstrated by the diastereoselective synthesis of C‐vinyl glycosides. Preliminary mechanistic studies suggest that the C−C bond formation is stereospecific and proceeds through a concerted radical coupling transition state. [ABSTRACT FROM AUTHOR]

The CO2 sorption properties of sodium hafnium oxide (Na2HfO3) were investigated in this study. Na2HfO3 was synthesized by solid-state synthesis using Na2CO3 and HfO2 as starting materials. The solid-state synthesized Na2HfO3 appeared structurally similar to other mixed metal oxides such as Na2ZrO3, but stacking disorder appeared to be common in Na2HfO3. The synthesis conditions, including the Na : Hf ratio (between 0.5 and 1.5 : 1), synthesis temperature, time and heating rate, were investigated to optimize CO2 sorption properties of Na2HfO3. The Na2HfO3 sorbent showed comparable CO2 uptake capacity, reaction rate and excellent cycling stability compared to other metal oxide sorbents. Na2HfO3 with Na : Hf = 1 : 1 and 1.25 : 1 showed the highest CO2 uptake among all Na2HfO3 samples obtained, with a CO2 uptake capacity of around 15 wt% (at 650–800 °C). The CO2 uptake rate of NHO-1 and NHO-1.25 was fast with over 80% of the equilibrium uptake reached within 250 s. Na2HfO3 remained stable even after 100 cycles with less than 3% difference in the CO2 uptake capacity between the 1st and 100th cycles. We performed kinetic analysis on the CO2 sorption data and found that the Avrami–Erofeev model fitted the kinetic data best among the kinetic models used. Apart from sorbent optimization, we showed that 3D-printing of Na2HfO3 : HfO2 mixtures can be used to produce structured Na2HfO3 sorbents with a slightly improved CO2 uptake rate and the same CO2 uptake capacity as the powder-based solid-state synthesized Na2HfO3 sorbent. [ABSTRACT FROM AUTHOR]

Mono- and a di-protonated pyridine type cations have been used for the synthesis of two bis(oxalato) cuprate(II) salts, namely, (C5H7N2O)2[Cu(C2O4)2] (C5H7N2O = 2-amino-3-hydroxypyridinium) 1 and C13H16-N2[Cu(C2O4)2] (C13H16N2 = 4,4'-trimethylenedipyridinium) 2. In the crystal structures, C2O42- adopts different coordination modes: the common bidentate chelating oxalate in 1 and the relatively scarce µ-oxalato-?³O¹,O²:O¹' in 2. X-ray diffraction also revealed that [Cu(C2O4)2]2- anions do not polymerize in 1 (a phenomenon hardly observed in such salts), while in 2, the polymerization of [Cu(C2O4)2]2- units occurs via the Cu-Oaxial contact forming a zigzag Cu(II) chain. In complex 1, the emerging building blocks are linked into 2D supramolecular layers via N-H···O and O-H···O hydrogen bonds and weaker C-H···O interaction to form a 3D net. In contrast to 2, the emerging building blocks are linked into 1D chains via N-H···O hydrogen bonds, which further extend to form a 3D supramolecular framework through Cu-Oaxial and other C-H···O interactions. The structural diversities show that iminium counterions play key roles in the construction of various architectures. Thermal analyses showed no weight loss for either system in the temperature range of 20-180 °C, which indicates that none of these complexes possess solvation water molecules. Magnetic studies indicate the presence of antiferromagnetic coupling between the spin centres in 1 and 2. [ABSTRACT FROM AUTHOR]

The effect of solvent has been investigated for the synthesis of bismuth gallate compounds, of which the water-based bismuth subgallate has been used as an active pharmaceutical ingredient (API) for over a century. Using methanol as a solvent, two new bismuth gallates were acquired: first a flexible 3-periodic metal–organic framework (MOF) forms, which transforms upon extended synthesis times into a layered 2-periodic coordination polymer of the same bismuth-to-gallate ratio. The structures were determined by three-dimensional electron diffraction. Synthesis in ethanol resulted in the formation of the MOF phase, but not the layered phase. The layered material of the methanol-based synthesis was used as a Lewis acid catalyst due to its higher stability, showing a comparatively quick and regiospecific conversion of styrene oxide to 2-methoxy-2-phenylethanol, indicating the presence of open metal sites in the material. The acquisition of bismuth gallate structures of varying periodicity highlights the prospect of acquiring novel MOFs and coordination polymers from the same components of APIs. [ABSTRACT FROM AUTHOR]

Bibrocathol is an active pharmaceutical ingredient that has been used to treat eyelid diseases for over a century, yet its structure has remained unknown. 3D electron diffraction on crystals from a commercial ointment revealed two structures. These results highlight the technique's potential in structure elucidation from microcrystalline mixtures. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) metal–organic frameworks (MOFs) have become a hot topic recently due to their high surface area, larger number of exposed active sites, and improved conductivity. Combining different 2D MOFs could introduce new physical and chemical properties. Here, we have synthesized a heteroepitaxially grown 2D zeolitic imidazolate framework with a leaf-like morphology (ZIF-L). ZIF-L has a layer-by-layer dense structure, which possesses a high content of N and metal ions as active sites. ZIF-L-Co is heteroepitaxially grown on ZIF-L-Zn, while ZIF-L-Zn@ZIF-Co has been successfully prepared. After pyrolysis, the heteroepitaxially grown MOF derived ultra-small Co nanoparticle immobilized nitrogen doped carbon (NC) material (HM-Co@NC) exhibits superior oxygen reduction reaction (ORR) activity (Eonset = 0.998 V, E1/2 = 0.905 V) and better stability than Pt/C, achieving well-qualified assemblies for use in rechargeable Zn–air batteries. [ABSTRACT FROM AUTHOR]

15 Loiseau, T., Serre, C., Huguenard, C., Fink, G., Taulelle, F., Henry, M., Bataille, T., Férey, G. Chem. Eur. J. 2004, 10, 1373-1382; https://doi.org/10.1002/chem.200305413. 26 Li, W.-J., Liu, J., Sun, Z.-H., Liu, T.-F., Lü, J., Gao, S.-Y., He, C., Cao, R., Luo, J.-H. Nat. 6 García-Sánchez, A., Gomez-Mendoza, M., Barawi, M., Villar-Garcia, I. J., Liras, M., Gándara, F., de la Peña O'Shea, V. A. J. Am. Chem. Soc. 2020, 142, 318-326; https://doi.org/10.1021/jacs.9b10261. 5 Lamagni, P., Miola, M., Catalano, J., Hvid, M. S., Mamakhel, M. A. H., Christensen, M., Madsen, M. R., Jeppesen, H. S., Hu, X.-M., Daasbjerg, K., Skrydstrup, T., Lock, N. Adv. Funct. [Extracted from the article]

Structure determination of pharmaceutical compounds is invaluable for drug development but remains challenging for those that form as small crystals with defects. Bismuth subsalicylate, among the most commercially significant bismuth compounds, is an active ingredient in over-the-counter medications such as Pepto-Bismol, used to treat dyspepsia and H. pylori infections. Despite its century-long history, the structure of bismuth subsalicylate is still under debate. Here we show that advanced electron microscopy techniques, namely three-dimensional electron diffraction and scanning transmission electron microscopy, can give insight into the structure of active pharmaceutical ingredients that are difficult to characterize using conventional methods due to their small size or intricate structural features. Hierarchical clustering analysis of three-dimensional electron diffraction data from ordered crystals of bismuth subsalicylate revealed a layered structure. A detailed investigation using high-resolution scanning transmission electron microscopy showed variations in the stacking of layers, the presence of which has likely hindered structure solution by other means. Together, these modern electron crystallography techniques provide a toolbox for structure determination of active pharmaceutical ingredients and drug discovery, demonstrated by this study of bismuth subsalicylate. Pepto-Bismol has been used to treat gastrointestinal disorders for over a century, yet the structure of its active ingredient is still under debate. Here, the authors apply electron crystallography to unveil the structure of bismuth subsalicylate. [ABSTRACT FROM AUTHOR]

Structure determination of pharmaceutical compounds is invaluable for drug development but remains challenging for those that form as small crystals with defects. Bismuth subsalicylate, among the most commercially significant bismuth compounds, is an active ingredient in over-the-counter medications such as Pepto-Bismol, used to treat dyspepsia and H. pylori infections. Despite its century-long history, the structure of bismuth subsalicylate is still under debate. Here we show that advanced electron microscopy techniques, namely three-dimensional electron diffraction and scanning transmission electron microscopy, can give insight into the structure of active pharmaceutical ingredients that are difficult to characterize using conventional methods due to their small size or intricate structural features. Hierarchical clustering analysis of three-dimensional electron diffraction data from ordered crystals of bismuth subsalicylate revealed a layered structure. A detailed investigation using high-resolution scanning transmission electron microscopy showed variations in the stacking of layers, the presence of which has likely hindered structure solution by other means. Together, these modern electron crystallography techniques provide a toolbox for structure determination of active pharmaceutical ingredients and drug discovery, demonstrated by this study of bismuth subsalicylate. Pepto-Bismol has been used to treat gastrointestinal disorders for over a century, yet the structure of its active ingredient is still under debate. Here, the authors apply electron crystallography to unveil the structure of bismuth subsalicylate. [ABSTRACT FROM AUTHOR]

Bismuth-based coordination polymers (CPs) have recently attracted attention as catalyst precursors for the electrocatalytic CO2 reduction reaction (eCO2RR). We present a comparative study by investigating six bismuth-based compounds in-depth to elucidate the correlation between their structures and their catalytic CO2-to-formate conversion. Thereby, we identify structural indicators of the pristine CPs resulting in optimized catalytic performance, paving the way for future design of CP derived catalysts. The structural properties of the six pristine materials vary in terms of porosity (from non-porous to 495 m2 g−1), linker type (carboxylate- or phenolate-based), thermal- and chemical stability, and metal content. Herein, electrochemical studies are combined with comprehensive structural investigations using electron microscopy, powder X-ray diffraction, and X-ray absorption spectroscopy. Our study reveals that low chemical stability of the pristine CPs is crucial for the conversion of the precursors into active Bi2O2CO3 and of paramount importance for the eCO2RR activity, while the nature of the pristine material mostly influence the catalyst morphology and transport properties. Of the six investigated CPs, the best performing compounds selectively convert CO2 to formate with faradaic efficiencies in the range 80(3)–95(3)% and current densities of 5(1)–8(1) mA cm−2 at −0.97 VRHE. [ABSTRACT FROM AUTHOR]

A series of olefin metathesis catalysts bearing cyclic (alkyl)(amino)carbene (CAAC) ligands of varying size and steric demand has been synthesized and evaluated in ring‐closing‐, self‐, and cross‐metathesis reactions at room temperature. The catalysts were also probed for potential applications in dynamic covalent chemistry. The majority of the catalysts showed high stability, and remained active in the reaction mixtures for several days, including in methanol‐based solutions. Higher temperatures could be used to control the reactivity towards sterically challenging substrates, enabling formation of tetrasubstituted olefins. The CAAC complexes exhibited remarkable functional group tolerance towards heteroaromatic and nucleophilic additives, making them potentially useful in the screening of biologically active compounds. [ABSTRACT FROM AUTHOR]

The reaction of the V‐shaped linker molecule 5‐hydroxyisophthalic acid (H2L0), with Al or Ga nitrate under almost identical reaction conditions leads to the nitration of the linker and subsequent formation of metal–organic frameworks (MOFs) with CAU‐10 or MIL‐53 type structure of composition [Al(OH)(L)], denoted as Al‐CAU‐10‐L0, 2, 4, 6 or [Ga(OH)(L)], denoted as Ga‐MIL‐53‐L2. The Al‐MOF contains the original linker L0 as well as three different nitration products (L2, L4 and L4/6), whereas the Ga‐MOF mainly incorporates the linker L2. The compositions were deduced by 1H NMR spectroscopy and confirmed by Rietveld refinement. In situ and ex situ studies were carried out to follow the nitration and crystallization, as well as the composition of the MOFs. The crystal structures were refined against powder X‐ray diffraction (PXRD) data. As anticipated, the use of the V‐shaped linker results in the formation of the CAU‐10 type structure in the Al‐MOF. Unexpectedly, the Ga‐MOF crystallizes in a MIL‐53 type structure, which is usually observed with linear or slightly bent linker molecules. To study the structure directing effect of the in situ nitrated linker, pure 2‐nitrobenzene‐1,3‐dicarboxylic acid (m‐H2BDC‐NO2) was employed which exclusively led to the formation of [Ga(OH)(C8H3NO6)] (Ga‐MIL‐53‐m‐BDC‐NO2), which is isoreticular to Ga‐MIL‐53‐L2. Density Functional Theory (DFT) calculations confirmed the higher stability of Ga‐MIL‐53‐L2 compared to Ga‐CAU‐10‐L2 and grand canonical Monte Carlo simulations (GCMC) are in agreement with the observed water adsorption isotherms of Ga‐MIL‐53‐L2. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is an efficient means of producing energy carriers, such as H2. The hydrogen evolution reaction (HER) requires high-efficiency electrocatalysts. Understanding the active site structures of the HER electrocatalysts is essential for the rational design and development of water splitting devices. In this study, porous CoW sulfides were employed as model electrocatalysts for pH-universal HER. Multiple characterization studies, such as X-ray photoelectron spectroscopy, X-ray absorption spectroscopy and operando X-ray diffraction, were systematically used to investigate the reconstruction of the active species at the surface and in the bulk. The results show that during the HER, the structural transformation of the species CoW sulfides is strongly dependent on the pH of the electrolyte. Electrolytes of varying pH lead to varied reconstruction and influence the true catalytically active species responsible for the HER. The surface and the bulk of the electrocatalysts transform to different oxides/hydroxides when subjected to the HER. This is the first time that the pH-dependent bulk and surface structural evolution in the HER has been revealed. This study reveals the reconstruction and potential active site evolution of mixed-metal sulfides for the HER. We believe that the present study not only provides an idealized "pre-catalyst" for pH-universal highly-efficient HER, but also provides a thorough understanding about the identification of the real active sites and the mechanism of the structural evolution of the electrocatalysts during hydrogen evolution. [ABSTRACT FROM AUTHOR]

Tuning the local environment of nanomaterial‐based catalysts has emerged as an effective approach to optimize their oxygen evolution reaction (OER) performance, yet the controlled electronic modulation around surface active sites remains a great challenge. Herein, directed electronic modulation of NiO nanoparticles was achieved by simple surface molecular modification with small organic molecules. By adjusting the electronic properties of modifying molecules, the local electronic structure was rationally tailored and a close electronic structure‐activity relationship was discovered: the increasing electron‐withdrawing modification readily decreased the electron density around surface Ni sites, accelerating the reaction kinetics and improving OER activity, and vice versa. Detailed investigation by operando Raman spectroelectrochemistry revealed that the electron‐withdrawing modification facilitates the charge‐transfer kinetics, stimulates the catalyst reconstruction, and promotes abundant high‐valent γ‐NiOOH reactive species generation. The NiO−C6F5 catalyst, with the optimized electronic environment, exhibited superior performance towards water oxidation. This work provides a well‐designed and effective approach for heterogeneous catalyst fabrication under the molecular level. [ABSTRACT FROM AUTHOR]

Electron and powder diffraction were combined to elucidate the structure of the new coordination polymer [Sc2(FcDC)3] based on 1,1′-ferrocenedicarboxylate (FcDC2−), denoted as CAU-50. Remarkably, three different conformers of the very same linker molecule are observed, two of which serve as connectors for the scandium cations while one conformer acts as capping agent. [ABSTRACT FROM AUTHOR]

A new scandium naphthalenedicarboxylate with the framework composition [Sc2(1,4‐NDC)3] (H2‐1,4‐NDC = 1,4‐naphthalenedicarboxylic acid) was obtained under hydrothermal synthesis conditions. A structure model could be developed by a combination of 3D electron diffraction measurements and computationally assisted structure determination, which was further validated by a good agreement with the experimental powder X‐ray diffraction pattern. The structure consists of isolated ScO6 octahedra interconnected by the carboxylate groups of linker molecules to form chains. These chains are connected by the naphthalene‐moieties to form a three‐dimensional framework with square‐shaped pores and the organic group pointing into the pores. Although very similar synthesis conditions were chosen, [Sc2(1,4‐NDC)3] is not isostructural to aluminum naphthalenedicarboxylate [Al(OH)(1,4‐NDC)], which crystallizes in a MIL‐53 type structure. This can be traced back to the different inorganic building units that are observed. The compound was thoroughly characterized by elemental analysis, IR spectroscopy, sorption measurements, thermogravimetric analysis and luminescence measurements. [Sc2(1,4‐NDC)3] exhibits a high thermal stability and a ligand‐based blue luminescence in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

A silver‐triggered heterogeneous Pd‐catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one‐pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd‐AmP‐CNC, thereby generating highly active PdII, which results in high efficiency of the heterogeneous catalytic system. [ABSTRACT FROM AUTHOR]

A silver‐triggered heterogeneous Pd‐catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one‐pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd‐AmP‐CNC, thereby generating highly active PdII, which results in high efficiency of the heterogeneous catalytic system. [ABSTRACT FROM AUTHOR]

A versatile strategy for the enantioselective synthesis of bicyclic lactam N,S‐acetals by one‐pot cascade transformations is disclosed. The transformation of readily available substrates is promoted by chiral amines and creates bicyclic or tricyclic lactam N,S‐acetals with high chemo‐ and stereoselectivity (up to > 99.5:0.5 dr and > 99 % ee) in one‐pot operations. [ABSTRACT FROM AUTHOR]

Single‐crystal electron diffraction has shown to be powerful for structure determination of nano‐ and submicron‐sized crystals that are too small to be studied by single‐crystal X‐ray diffraction. However, it has been very challenging to obtain high quality electron diffraction data from beam sensitive crystals such as metal–organic frameworks (MOFs). It is even more difficult to locate guest species in the pores of MOF crystals. Here, we present synthesis of a novel porous cobalt MOF with 1D channels, [Co2(Ni‐H4TPPP)]⋅2 DABCO⋅6 H2O, (denoted Co‐CAU‐36; DABCO=1,4‐diazabicyclo[2.2.2]octane), and its structure determination using continuous rotation electron diffraction (cRED) data. By combining a fast hybrid electron detector with low sample temperature (96 K), high resolution (0.83–1.00 Å) cRED data could be obtained from eight Co‐CAU‐36 crystals. Independent structure determinations were conducted using each of the eight cRED datasets. We show that all atoms in the MOF framework could be located. More importantly, we demonstrate for the first time that organic molecules in the pores, which were previously difficult to find, could be located using the cRED data. A comparison of eight independent structure determinations using different datasets shows that structural models differ only on average by 0.03(2) Å for the framework atoms and 0.10(6) and 0.16(12) Å for DABCO and water molecules, respectively. Continuous‐rotation electron diffraction (cRED) was used as a stand‐alone method for both structure solution and refinement of submicron‐sized crystals of a novel cobalt metal–organic framework. We show that the method is robust; not only the framework structure, but also solvent molecules in the pores could be precisely located. [ABSTRACT FROM AUTHOR]

Vanillic acid, C8H8O4, is a possible product from a future biorefinery with lignin as raw material. Two coordination compounds with this ligand in two different protonation states were prepared: 1 [Zn(C8H7O4)2(H2O)2] and 2 [Co2(C8H6O4)2(H2O)6] ⋅ 2H2O. Both compounds form extended 3D structures with strong hydrogen bonds. A high symmetry 8‐ and 4‐connected network topology, jus, is found in 1. The dinuclear coordination entity in 2 hints at a potentially useful SBU for MOF synthesis from lignin based bridging ligands. [ABSTRACT FROM AUTHOR]

Two novel dopant-free hole-transport materials (HTMs) with spiro[dibenzo[c,h]xanthene-7,9′-fluorene] (SDBXF) skeletons were prepared via facile synthesis routes. A power conversion efficiency of 15.9% in perovskite solar cells is attained by using one HTM without dopants, which is much higher than undoped Spiro-OMeTAD-based devices (10.8%). The crystal structures of both new HTMs were systematically investigated to reveal the reasons behind such differences in performance and to indicate the design principles of more advanced HTMs. [ABSTRACT FROM AUTHOR]

Very few microporous bismuth metal‐organic frameworks have been discovered to date. Of these, no detailed experimental characterization of the synthesis and properties have been reported until now for the only one which can be prepared from inexpensive starting materials: CAU‐17 [Bi(BTC)(H2O)], with H3BTC = trimesic acid. In‐situ powder X‐ray diffraction during solvothermal synthesis of CAU‐17 revealed that it crystallizes rapidly within 2 minutes, and if the reaction is not stopped, the MOF transforms into a nonporous dense purely inorganic material within one hour, revealing that CAU‐17 is a crystalline intermediate phase. Synthesis scale‐up employing more concentrated reaction mixtures resulted in another Bi trimesate of composition [Bi(HBTC)(NO3)(MeOH)]·MeOH, which structurally decomposes upon storage under ambient conditions. Sorption experiments showed that CAU‐17 is microporous with a BET surface area of 530 m2/g. As a potential greenhouse gas sorbent, CAU‐17 showed high SF6/N2 and CO2/N2 selectivity > 31 and 29, respectively. Furthermore, the catalytic activity of CAU‐17 was studied in the regioselective ring‐opening of styrene oxide by methanol to obtain 2‐methoxy‐2‐phenylethanol, thus demonstrating the existence of coordinatively unsaturated sites in the crystal structure of CAU‐17. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report a versatile carbonylation protocol using heterogeneous Pd0 nanoparticles supported on the metal–organic frameworks (MOFs) MIL‐88B‐NH2 (Fe/Cr). The synthesis of a vast array of carbonyls, which includes amides, esters, carboxylic acids, and α‐ketoamides, was achieved through mono‐ and dicarbonylation reactions. The selectivity could be controlled simply by tuning the reaction conditions. Superior activity and selectivity were recorded in some cases compared to that achieved with commercial Pd/C. However, the utility of an elaborate catalyst support is questionable and important reactivity and recyclability issues are discussed. [ABSTRACT FROM AUTHOR]

A new versatile and easy-to-use remote-controlled reactor setup aimed at the analysis of chemical reactions under solvothermal conditions has been constructed. The reactor includes a heating system that can precisely control the temperature inside the reaction vessels in a range between ambient temperature and 180 °C. As reaction vessels, two sizes of commercially available borosilicate vessels (Vmax = 5 and 11 ml) can be used. The setup furthermore includes the option of stirring and injecting of up to two liquid additives or one solid during the reaction to initiate very fast reactions, quench reactions, or alter chemical parameters. In addition to a detailed description of the general setup and its functionality, three examples of studies conducted using this setup are presented. [ABSTRACT FROM AUTHOR]

Three new In-MOFs with –NH2 and/or –NO2 functionalities are reported using 2-amino- (H2BDC-NH2), 2-nitro- (H2BDC-NO2) and 2-amino-5-nitroterephthalic acid (H2BDC-NH2/NO2). Their structures were determined from single crystal X-ray diffraction data. The structure of the first In-MOF of composition [In(BDC-NH3)(BDC-NH2)]·1.6DMF·1.9H2O (In-BDC-NH2; DMF is dimethylformamide; the space group is P6222, a = b = 14.738(2) Å and c = 12.257(3) Å) is built up by two interpenetrating nets of InO8 polyhedra interconnected by BDC-NH22− ions to form a framework with qtz topology. Charge balance is accomplished by partial protonation of the amino group, which was confirmed by IR spectroscopy. The interpenetration leads to a decrease of the pore dimension (4.4 Å in diameter). Thermogravimetric analysis revealed stability up to 300 °C. Replacement of H2BDC-NH2 by H2BDC-NO2 in the reaction mixture led to the isoreticular MOF containing no –NO2 groups but exclusively un- and amino-functionalized linkers. Hence an indium mediated reduction of the H2BDC-NO2 linker molecule during solvothermal synthesis has occurred. The use of H2BDC-NH2/NO2 under exactly the same reaction conditions did not result in the formation of a MOF, but by changing the synthesis parameters, a new –NH2/–NO2 bifunctionalised In-MOF of composition (DMA)2[In3(μ3-O)(BDC-NH2/NO2)4.5]·DMF (DMA is dimethylammonium), denoted In-BDC-NH2/NO2, was obtained. The crystal morphology can be altered from cubic to truncated octahedral crystals by varying the DMF/ethanol volume ratio during synthesis. The compound crystallises in the cubic space group I4̅3m, a = 24.8947(1) Å, and the framework contains trinuclear {In3(μ3-O)} clusters which are interlinked by the BDC-NH2/NO22− ions to form super-tetrahedra. Four face-sharing super-tetrahedra form ultra-tetrahedra which are connected to form the final cubic framework with an ncb topology and isolated inaccessible pores. [ABSTRACT FROM AUTHOR]

We report the modular formulation of ciprofloxacin-based pure theranostic nanodrugs that display enhanced antibacterial activities, as well as aggregation-induced emission (AIE) enhancement that was successfully used to image bacteria. The drug derivatives, consisting of ciprofloxacin, a perfluoroaryl ring, and a phenyl ring linked by an amidine bond, were efficiently synthesized by a straightforward protocol from a perfluoroaryl azide, ciprofloxacin, and an aldehyde in acetone at room temperature. These compounds are propeller-shaped, and upon precipitation into water, readily assembled into stable nanoaggregates that transformed ciprofloxacin derivatives into AIE-active luminogens. The nanoaggregates displayed increased luminescence and were successfully used to image bacteria. In addition, these nanodrugs showed enhanced antibacterial activities, lowering the minimum inhibitory concentration (MIC) by more than one order of magnitude against both sensitive and resistant Escherichia coli. The study represents a strategy in the design and development of pure theranostic nanodrugs for combating drug-resistant bacterial infections. [ABSTRACT FROM AUTHOR]

Bismuth subgallate has been used in wound and gastrointestinal therapy for over a century. The combination of continuous rotation electron diffraction and sample cooling finally revealed its structure as a coordination polymer. The structure provides insight regarding its formula, poor solubility, acid resistance and previously unreported gas sorption properties. [ABSTRACT FROM AUTHOR]

The crystal structure of a novel open-framework gallogermanate, SU-66 {|(C6H18N2)18(H2O)32|[Ga4.8Ge87.2O208]}, has been solved from laboratory X-ray powder diffraction (XPD) data by using a direct-space structure solution algorithm and local structural information obtained from infrared (IR) spectroscopy. IR studies on 18 known germanates revealed that the bands in their IR spectra were characteristic of the different composite building units (CBUs) present in the structures. By comparing the bands corresponding to Ge-O vibrations in the IR spectra of SU-66 with those of the 18 known structures with different CBUs, the CBU of SU-66 could be identified empirically as the Ge10(O,OH)27 cluster (Ge10). The unit cell and space group (extinction symbol P-- a; a = 14.963, b = 31.593, c = 18.759 Å) were determined initially from the XPD pattern and then confirmed by selected-area electron diffraction. The structure of SU-66 was solved from the XPD data using parallel tempering as implemented in FOX [Favre-Nicolin & Černý (2002). J. Appl. Cryst. 35, 734-743] by assuming P21 ma symmetry and two Ge10 clusters in the asymmetric unit. Rietveld refinement of the resulting structure using synchrotron XPD data showed the framework structure to be correct and the space group to be Pmma. The framework has extra-large (26-ring) one-dimensional channels and a very low framework density of 10.1 Ge/Ga atoms per 1000 Å3. SU-66, with 55 framework atoms in the asymmetric unit, is one of the more complicated framework structures solved from XPD data. Indeed, 98% of the reflections were overlapping in the XPD pattern used for structure solution. Tests on other open-framework germanates (SU-62, SU-65, SU-74, PKU-12 and ITQ-37) for which the XPD data, unit cell, space group and IR spectra were available proved to be equally successful. In a more complex case (SU-72) the combination of FOX and powder charge flipping was required for structure solution. [ABSTRACT FROM AUTHOR]

A series of new iridium(III) complexes containing bidentate N-heterocyclic carbenes (NHC) functionalized with an alcohol or ether group (NHCOR, R=H, Me) were prepared. The complexes catalyzed the alkylation of anilines with alcohols as latent electrophiles. In particular, biscationic IrIII complexes of the type [Cp*(NHC-OH)Ir(MeCN)]2+2[BF4−] afforded higher-order amine products with very high efficiency; up to >99 % yield using a 1:1 ratio of reactants and 1-2.5 mol % of Ir, in short reaction times (2-16 h) and under base-free conditions. Quantitative yields were also obtained at 50 °C, although longer reaction times (48-60 h) were needed. A large variety of aromatic amines have been alkylated with primary and secondary alcohols. The reactivity of structurally related iridium(III) complexes was also compared to obtain insights into the mechanism and into the structure of possible catalytic intermediates. The IrIII complexes were stable towards oxygen and moisture, and were characterized by NMR, HRMS, single-crystal X-ray diffraction, and elemental analyses. [ABSTRACT FROM AUTHOR]

Aluminium, framework flexibility, gallium, molecular simulations, water adsorption Keywords: aluminium; framework flexibility; gallium; molecular simulations; water adsorption EN aluminium framework flexibility gallium molecular simulations water adsorption 7591 7591 1 05/20/21 20210517 NES 210517 B Starting from 5-hydroxyisophthalic acid b (not shown), in situ nitration leads to different nitrated linker molecules that selectively react with Ga SP 3+ sp or Al SP 3+ sp ions to Ga-MIL-53 and Al-CAU-10 type frameworks, respectively. Cover Feature: Metal-Dependent and Selective Crystallization of CAU-10 and MIL-53 Frameworks through Linker Nitration (Chem. Eur. J. 28/2021). [Extracted from the article]

Keywords: catalyst self-reconstruction; electrocatalysis; molecular modification; nanomaterials; water oxidation EN catalyst self-reconstruction electrocatalysis molecular modification nanomaterials water oxidation 5774 5774 1 11/23/20 20201120 NES 201120 B The Cover Feature b shows an efficient NiO-C SB 6 sb F SB 5 sb water oxidation catalyst, which was constructed by molecular functionalization at the nanoparticle surface. Catalyst self-reconstruction, electrocatalysis, molecular modification, nanomaterials, water oxidation. [Extracted from the article]

Highlights from the article: Cover Feature: Catalytic Enantioselective Synthesis of Bicyclic Lactam N,S-Acetals in One Pot by Cascade Transformations (Eur. J. Org. B The Cover Feature b shows a versatile strategy for the enantioselective synthesis of bicyclic lactam I N i , I S i -acetals by one-pot cascade transformations. B The Cover Feature b shows a versatile strategy for the enantioselective synthesis of bicyclic lactam I N i , I S i -acetals by one-pot cascade transformations.