Ruthenium-Catalyzed Dehydrogenation Through an Intermolecular Hydrogen Atom Transfer Mechanism

Lin Huang, Dr. Alessandro Bismuto, Simon A. Rath, Dr. Nils Trapp, Prof. Dr. Bill Morandi

An approach to the catalytic dehydrogenation of alkanes and heterocycles uses Ru and redox-active ligands. A wide range of functionalized substrates afforded dehydrogenated products in good yields. Preliminary mechanistic studies suggest that a redox-active ligand-assisted intermolecular hydrogen atom transfer is crucial to this process.

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Practical and Selective sp³ C−H Bond Chlorination via Aminium Radicals

Alastair J. McMillan, Martyna Sieńkowska, Piero Di Lorenzo, Dr. Gemma K. Gransbury, Dr. Nicholas F. Chilton, Prof. Michela Salamone, Dr. Alessandro Ruffoni, Prof. Massimo Bietti, Prof. Daniele Leonori

Direct and selective sp³ C−H chlorination has been achieved using a photoinduced strategy. This approach is based on a radical-chain propagation that exploits the ability of aminium radicals to undergo site-selective H-atom transfer (HAT).

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Advanced Real-Time Process Analytics for Multistep Synthesis in Continuous Flow

Peter Sagmeister, René Lebl, Dr. Ismael Castillo, Dr. Jakob Rehrl, Dr. Julia Kruisz, Martin Sipek, Prof. Dr. Martin Horn, Dr. Stephan Sacher, Dr. David Cantillo, Dr. Jason D. Williams, Prof. Dr. C. Oliver Kappe

Process analytical technologies hold tremendous promise in multistep continuous flow synthesis. Here, four orthogonal real-time analytical tools are employed in a three step synthesis, with phase separations. Advanced data processing techniques, such as indirect hard modeling and deep learning, facilitate quantification of up to 9 process components. These analytical capabilities are demonstrated for both steady state and dynamic experiments.

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Hexagonal RuSe₂ Nanosheets for Highly Efficient Hydrogen Evolution Electrocatalysis

Yuanmeng Zhao, Prof. Dr. Hengjiang Cong, Peng Li, Dean Wu, Prof. Dr. Shengli Chen, Prof. Dr. Wei Luo

Hexagonal RuSe₂ nanosheets (h-RuSe₂), including 2H and 1T phases, are prepared in a one-pot colloidal synthesis. This new member of the family of layered transition metal dichalcogenides (TMDs) displays significantly enhanced HER performance. The structural phase change from h-RuSe₂ to cubic RuSe₂ takes place upon annealing at 600 °C. This is a significant step forward in expanding the family of layered TMDs.

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Non-Metal Ion Co-Insertion Chemistry in Aqueous Zn/MnO₂ Batteries

Dr. Shuai Wang, Dr. Zishun Yuan, Dr. Xu Zhang, Songshan Bi, Prof. Zhen Zhou, Prof. Jinlei Tian, Prof. Qichun Zhang, Prof. Zhiqiang Niu

A reversible H⁺/NH₄⁺ co-insertion/extraction mechanism was developed in an aqueous Zn/MnO₂ battery system. The co-insertion of H⁺/NH₄⁺ ions in MnO₂ endows the aqueous batteries with the fast kinetics of ion diffusion and the reversible structure evolution of MnO₂ due to the synergistic effect between the dual cations. As a result, such Zn/MnO₂ batteries display enhanced electrochemical performance.

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Unveiling the Electrooxidation of Urea: Intramolecular Coupling of the N−N Bond

Wei Chen, Leitao Xu, Xiaorong Zhu, Yu-Cheng Huang, Wang Zhou, Dongdong Wang, Yangyang Zhou, Shiqian Du, Qiling Li, Chao Xie, Li Tao, Prof. Chung-Li Dong, Jilei Liu, Yanyong Wang, Ru Chen, Hui Su, Chen Chen, Yuqin Zou, Prof. Yafei Li, Qinghua Liu, Prof. Shuangyin Wang

During urea electrooxidation over a Ni(OH)₂ electrode the dehydrogenation reaction from β-Ni(OH)₂ to β-Ni(OH)O can lead to spontaneous urea dehydrogenation. Spontaneous intramolecular coupling of the N−N bond and hydration of urea dehydrogenation intermediates play important roles in the oxidation path from urea to N₂ and CO₂.

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Photochemical Electrocyclization of Poly(phenylacetylene)s: Unwinding Helices to Elucidate their 3D Structure in Solution

Francisco Rey-Tarrío, Dr. Rafael Rodríguez, Prof. Dr. Emilio Quiñoá, Prof. Dr. Ricardo Riguera, Prof. Dr. Félix Freire

The photochemical electrocyclization of poly(phenylacetylene)s in solution was utilized to obtain important structural information that allows determine their helical structures (cis-cisoidal (ω₁<90°) or cis-transoidal (ω₁>90°)) while it also provides an estimated value of ω₁. When applied to mixtures, it allows the identification of the different helical scaffolds that coexist in solution.

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Stanene-Based Nanosheets for β-Elemene Delivery and Ultrasound-Mediated Combination Cancer Therapy

Dr. Wei Chen, Chuang Liu, Dr. Xiaoyuan Ji, Dr. John Joseph, Dr. Zhongmin Tang, Dr. Jiang Ouyang, Yufen Xiao, Dr. Na Kong, Prof. Dr. Nitin Joshi, Prof. Dr. Omid C. Farokhzad, Prof. Dr. Wei Tao, Prof. Dr. Tian Xie

2D stanene-based nanosheets (SnNSs) obtained by a liquid-phase exfoliation strategy could serve as a new type of sonosensitizer for ultrasound-mediated sonodynamic therapy (SDT). In addition, SnNSs could serve as robust photothermal agents and carriers for photothermal therapy (PTT) and β-elemene delivery. This study not only presents a robust strategy for the large-scale synthesis of SnNSs but also establishes general platforms for tri-modal combination cancer therapy.

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Amine-to-Azide Conversion on Native RNA via Metal-Free Diazotransfer Opens New Avenues for RNA Manipulations

Dr. Olga A. Krasheninina, Julia Thaler, Prof. Dr. Matthias D. Erlacher, Prof. Dr. Ronald Micura

Metal-free diazotransfer on native RNA using the reagent FSO₂N₃ selectively provides azide-modified RNA in quantitative yields. The stereochemically controlled reaction opens new avenues for the synthesis of RNA-peptide conjugates and for the isolation of cellular RNA containing post-transcriptional nucleotide modifications with an aliphatic primary amino group, such as acp³U.

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Delicate Control on the Shell Structure of Hollow Spheres Enables Tunable Mass Transport in Water Splitting

Dr. Ping Hou, Dr. Dan Li, Prof. Nailiang Yang, Prof. Jiawei Wan, Dr. Chunhui Zhang, Prof. Xiqi Zhang, Dr. Hongyu Jiang, Prof. Qinghua Zhang, Prof. Lin Gu, Prof. Dan Wang

With a simple phosphorization process, we can effectively modify the shell from solid to bubble-like and even duplicate the shell numbers with a narrow cavity between shells. Benefiting from the structure merits, the fabricated CoP hollow multishell structures (HOMSs) with bubble-like shells and close duplicated shells can both form an effectively unique channel of water and gas, which can efficiently accelerate the entry of liquid and gas release.

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Tuning the H-Atom Transfer Reactivity of Iron(IV)-Oxo Complexes as Probed by Infrared Photodissociation Spectroscopy

Guilherme L. Tripodi, Magda M. J. Dekker, Prof. Dr. Jana Roithová, Prof. Dr. Lawrence Que Jr.

The reaction kinetics of H-atom transfer mediated by iron(IV)oxo complexes with different cis-ligands can be studied in a modular flow reactor coupled to MS detection. The HAT reactivity correlates with the intrinsic properties of the isolated complexes in the gas phase. A ligand with a larger binding energy forms a more reactive complex for the HAT reactions, has a weaker Fe^IV=O bond, and forms a stronger Fe^IIIO−H bond after the HAT reaction.

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Covalent Cell Surface Conjugation of Nanoparticles by a Combination of Metabolic Labeling and Click Chemistry

Alexander Lamoot, Annemiek Uvyn, Dr. Sabah Kasmi, Prof. Dr. Bruno G. De Geest

Live cells can be efficiently conjugated with nanoparticles on their surface by two successive biorthogonal click reactions. The 2-step method yields a highly specific cell surface conjugation of ligand-decorated nanoparticles, with very low non-specific background binding.

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Fast Li-Ion Conductivity in Superadamantanoid Lithium Thioborate Halides

Kavish Kaup, Abdeljalil Assoud, Jue Liu, Linda F. Nazar

A new class of lithium thioborate halides adopt an adamantanoid structure that houses mobile lithium ions within interconnected 3D structural channels and exhibit high ionic conductivities up to 1.4 mS cm⁻¹, which can be effectively tuned by the polarizability of the halide anion within the channels.

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Side-on Coordination in Isostructural Nitrous Oxide and Carbon Dioxide Complexes of Nickel

Braulio M. Puerta Lombardi, Dr. Chris Gendy, Dr. Benjamin S. Gelfand, Dr. Guy M. Bernard, Prof. Roderick E. Wasylishen, Prof. Heikki M. Tuononen, Prof. Roland Roesler

The characterization of η²-N,N′-N₂O and CO₂ complexes of nickel and the associated computational study reveal that the bonding ability of N₂O to nickel is intermediate between that of CO₂ and that of H₂C=CH₂. It is shown that in general, N₂O η²-binds to metals comparably to or stronger than CO₂, indicating that the rarity of η²-N₂O metal complexes is due mostly to its oxidizing character and not to its weak σ-donating and π-accepting properties.

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Locally Ordered Graphitized Carbon Cathodes for High-Capacity Dual-Ion Batteries

Kai Yang, Dr. Qirong Liu, Dr. Yongping Zheng, Hang Yin, Prof. Shanqing Zhang, Prof. Yongbing Tang

Locally ordered graphitized carbon (LOGC), interconnected with disordered carbon, is able to weaken the van der Waals interactions between adjacent graphene sheets and thus reduce the anion-intercalating voltage. Conversely, disordered carbon not only interconnects the dispersed nanographite but also partially buffer severe anion-anion repulsions and offer extra capacitive anion storage sites.

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Non-Coordinative Binding of O₂ at the Active Center of a Copper-Dependent Enzyme

Florian Leisinger, Dzmitry A. Miarzlou, Prof. Dr. Florian P. Seebeck

Structural evidence suggests that the formylglycine generating enzyme binds O₂ juxtaposed but not coordinated to the copper-center prior to any redox activity.

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Interaction with Ribosomal Proteins Accompanies Stress Induction of the Anticancer Metallodrug BOLD-100/KP1339 in the Endoplasmic Reticulum

Benjamin Neuditschko, Dr. Anton A. Legin, Dina Baier, Arno Schintlmeister, Prof. Dr. Siegfried Reipert, Prof. Dr. Michael Wagner, Prof. Dr. Bernhard K. Keppler, Prof. Dr. Walter Berger, Priv.-Doz. Dr. Samuel M. Meier-Menches, Prof. Dr. Christopher Gerner

Multi-omics analysis, including affinity proteomics, revealed that the anticancer drug candidate BOLD-100/KP1339 may target the ribosomal proteins RPL10/RPL24 and GTF2I. Swelling of the endoplasmic reticulum (ER) and the observation of polyribosomes using imaging techniques indicate that BOLD-100 treatment may not only inhibit proliferation, but also lead to a functional disturbance of the ER.

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In Vivo Assembly of Artificial Metalloenzymes and Application in Whole-Cell Biocatalysis

Shreyans Chordia, Dr. Siddarth Narasimhan, Dr. Alessandra Lucini Paioni, Prof. Dr. Marc Baldus, Prof. Dr. Gerard Roelfes

Artificial metalloenzymes were created by supramolecular assembly in the cytoplasm of E. coli cells. The cells were then applied to the enantioselective biocatalysis of a Friedel-Crafts alkylation of indoles (see picture) and a Diels-Alder reaction. Directed evolution of the artificial metalloenzymes inside the cells provided improved variants for both whole-cell biocatalytic reactions.

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Activatable Polymeric Nanoprobe for Near-Infrared Fluorescence and Photoacoustic Imaging of T Lymphocytes

Prof. Yan Zhang, Dr. Shasha He, Wan Chen, Yinghua Liu, Xuefei Zhang, Prof. Qingqing Miao, Prof. Kanyi Pu

An activatable semiconducting polymer nanoprobe (SPNP) is synthesized for near-infrared fluorescence (NIRF) and photoacoustic (PA) detection of granzyme B, a biomarker related to activation of cytotoxic T lymphocytes. SPNP actively targets the tumor and reacts with granzyme B to release the dye-labeled peptide, leading to ratiometric NIRF/PA imaging of T lymphocytes during cancer immunotherapy.

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Fe-O Clusters Anchored on Nodes of Metal-Organic Frameworks for Direct Methane Oxidation

Wenshi Zhao, Yanan Shi, Yuheng Jiang, Dr. Xiaofei Zhang, Chang Long, Dr. Pengfei An, Dr. Yanfei Zhu, Shengxian Shao, Zhuang Yan, Prof. Guodong Li, Prof. Zhiyong Tang

Fe-O clusters are synthesized on nodes of UiO-66 simultaneously coordinated with trifluoroacetic acid (TFA) or acetic acid (AA) for direct methane oxidation. The TFA group coordinated with Zr₆ node of UiO-66 enhances the oxidation state of adjacent Fe-O cluster, promotes the activation of C−H bond of methane, and increases its selective conversion into C1 oxygenates.

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Silver Single-Atom Catalyst for Efficient Electrochemical CO₂ Reduction Synthesized from Thermal Transformation and Surface Reconstruction

Dr. Ningqiang Zhang, Xinxin Zhang, Dr. Lei Tao, Dr. Peng Jiang, Dr. Chenliang Ye, Dr. Rui Lin, Prof. Zhiwei Huang, Dr. Ang Li, Dawei Pang, Dr. Han Yan, Dr. Yu Wang, Dr. Peng Xu, Dr. Sufeng An, Dr. Qinghua Zhang, Prof. Licheng Liu, Prof. Shixuan Du, Prof. Xiaodong Han, Prof. Dingsheng Wang, Prof. Yadong Li

Silver nanoparticles converted into single atoms bring about a significant improvement in electrocatalytic CO₂ reduction with a 95.7 % faradic efficiency for CO production.

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Spectroscopic Verification of Adsorbed Hydroxy Intermediates in the Bifunctional Mechanism of the Hydrogen Oxidation Reaction

Yao-Hui Wang, Xiao-Ting Wang, Huajie Ze, Dr. Xia-Guang Zhang, Petar M. Radjenovic, Yue-Jiao Zhang, Jin-Chao Dong, Prof. Zhong-Qun Tian, Prof. Jian-Feng Li

HOR on Au@PtNi surfaces in alkaline media has been investigated by in situ surface-enhanced Raman spectroscopy (see picture). Direct spectroscopic evidence for OH_ad species was observed and further confirmed by deuterium isotopic experiments and DFT.

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Rational Fabrication of Crystalline Smart Materials for Rapid Detection and Efficient Removal of Ozone

Dong Yan, Zhifang Wang, Prof. Peng Cheng, Prof. Yao Chen, Prof. Zhenjie Zhang

We demonstrated the first example to use imine-based covalent organic frameworks (COFs) for smart sensing and efficient removal of ozone, and showed that the COFs’ performance could surpass traditional materials. The mechanism for the performance of imine-based COFs is unveiled.

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Structural Characterization of Two CO Molecules Bound to the Nitrogenase Active Site

Dr. Trixia M. Buscagan, Dr. Kathryn A. Perez, Ailiena O. Maggiolo, Prof. Douglas C. Rees, Dr. Thomas Spatzal

Besides reducing dinitrogen, nitrogenases reduce CO to hydrocarbons, mediating C−C bond formation between multiple CO-derived ligands. To shed light on how multiple C-based ligands bind to the active site, we report a 1.33 Å resolution crystal structure of two CO ligands coordinated to the FeMo-cofactor of molybdenum nitrogenase (see picture). The second CO ligand is coordinated to Fe6 in a previously unreported ligand binding mode.

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[Mo₃S₁₃]²⁻ as a Model System for Hydrogen Evolution Catalysis by MoS_x: Probing Protonation Sites in the Gas Phase by Infrared Multiple Photon Dissociation Spectroscopy

Aristeidis Baloglou, Manuel Plattner, Dr. Milan Ončák, Marie-Luise Grutza, Prof. Dr. Philipp Kurz, Prof. Dr. Martin K. Beyer

The cluster compound [Mo₃S₁₃]²⁻ is an interesting model system for hydrogen evolution catalysis. Herein, we probe the protonation site of the cluster by coupling mass spectrometry with infrared action spectroscopy. One distinct band at 2450 cm⁻¹ together with DFT calculations and IRMPD kinetics reveals the nature of this S−H stretching vibration.

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Mild and Robust Stille Reactions in Water using Parts Per Million Levels of a Triphenylphosphine-Based Palladacycle

Dr. Balaram S. Takale, Dr. Ruchita R. Thakore, Gianluca Casotti, Xaiohan Li, Dr. Fabrice Gallou, Prof. Dr. Bruce H. Lipshutz

Highly valued Stille couplings can now be done not only in water under mild reaction conditions, but with only 500-1000 ppm of Pd ligated with triphenylphosphine, derived from a new and readily prepared palladacycle.

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Porphyrinic Zirconium Metal-Organic Frameworks (MOFs) as Heterogeneous Photocatalysts for PET-RAFT Polymerization and Stereolithography

Liwen Zhang, Xiaobing Shi, Zhiheng Zhang, Dr. Rhiannon P Kuchel, Dr. Rashin Namivandi-Zangeneh, Dr. Nathaniel Corrigan, Dr. Kenward Jung, Dr. Kang Liang, Prof. Cyrille Boyer

Porphyrinic zirconium MOFs act as heterogeneous photocatalysts for photoinduced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of various monomers under a broad range of wavelengths, producing polymers with high monomer conversions, narrow molecular weight distributions, low dispersity and good chain-end fidelity

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Racemic Monomer-Based One-Handed Helical Polymer Recognizes Enantiomers through Auto-Evolution of Its Helical Handedness Excess

Dr. Tomoyuki Ikai, Tomoyuki Kurake, Shogo Okuda, Prof. Katsuhiro Maeda, Prof. Eiji Yashima

A racemic monomer-based polyacetylene folds into a one-handed helix assisted by a nonracemic alcohol through auto-evolution of its helical handedness over time, accompanied by successive enhancement of its optical purity adsorbed on the helical polyacetylene. The one-handed helical polyacetylene with the static helicity memory separates various enantiomers in liquid chromatography.

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