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Juraj Konč, Libby Brown, Daniel R. Whiten, Yukun Zuo, Peter Ravn, David Klenerman,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109713

Abstract:
Many bioconjugation strategies for DNA oligonucleotides and antibodies suffer limitations, such as site-specificity, stoichiometry and hydrolytic instability of the conjugates, which makes them unsuitable for biological applications. Here, we report a new platform for the preparation of DNA-antibody bioconjugates with a simple benzoylacrylic acid pentafluorophenyl ester reagent. Benzoylacrylic-labelled oligonucleotides prepared with this reagent can be site-specifically conjugated to a range of proteins and antibodies through accessible cysteine residues. The homogeneity of the prepared DNA-antibody bioconjugates was confirmed by a new LC–MS protocol and the bioconjugate probes were used in fluorescence or super-resolution microscopy cell imaging experiments. This work demonstrates the versatility and robustness of our bioconjugation protocol that gives site-specific, well-defined and plasma-stable DNA-antibody bioconjugates for biological applications.
, Qian-Jin An, Wang Xia, Wei-Yi Ding, Huan-Huan Liu, Shao-Hua Xiang, Yong-Bin Wang, Guofu Zhong
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111251

Abstract:
Described herein is an imidazole ring formation strategy for the synthesis of axially chiral N-arylbenzimidazoles by means of chiral phosphoric acid catalysis. Two sets of conditions were developed to transform two classes of 2-naphthylamine derivatives into structurally diverse N-arylbenzimidazole atropisomers with excellent chemo- and regioselectivity as well as high levels of enantiocontrol. It is worth reflecting on the unique roles played by the nitroso group in this domino reaction. It functions as a linchpin by first offering an electrophilic site (N) for the initial C-N bond formation while the resulting amine performs the nucleophilic addition to form the second C-N bond. Additionally, it could facilitate the final oxidative aromatization as an oxidant. The atropisomeric products could be conveniently elaborated to a series of axially chiral derivatives, enabling the exploitation of N-arylbenzimidazoles for their potential utilities in asymmetric catalysis.
Dennis Meier, Abhishek K. Adak, Peter Knecht, Joachim Reichert, Sourav Mondal, Nithin Suryadevara, Kuppusamy Senthil Kumar, Keitaro Eguchi, Matthias K. Muntwiler, Francesco Allegretti, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202107708

Abstract:
Tailored nano-spaces can control enantioselective adsorption and molecular motion. We report on the spontaneous assembly of a dynamic one-component system — a rigid kagome network with each pore occupied by a guest molecule — employing solely 2,6-bis(1H-pyrazol-1-yl)pyridine-4-carboxylic acid on Ag(111). The network cavity snugly hosts the guest, bestows enantiomorphic adsorption and allows selective rotational motions. Temperature-dependent scanning tunnelling microscopy studies revealed distinct anchoring orientations of the guest unit switching with a 0.95 eV thermal barrier. H-bonding between the guest and the host transiently stabilizes the rotating guest, as the flapper on a raffle wheel. Density functional theory investigations unravel the detailed molecular pirouette of the guest and how the energy landscape is determined by H-bond formation and breakage. The origin of the guest’s enantiodirected, dynamic anchoring lies in the specific interplay of the kagome network and the silver surface.
Jianan Li, Jili Li, Tao Liu, Lin Chen, Yefei Li, Hualin Wang, Xiurong Chen, Ming Gong, Zhi-Pan Liu,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202107886

Abstract:
Urea electrolysis is a prospective technology for simultaneous H2 production and nitrogen abatement toward water-energy nexus. Its sustainability is currently founded on the innocuous N2 products; however, herein, we discovered the prevalent nickel-based catalysts could generally over-oxidize urea into NO2- products with ~80% Faradaic efficiencies, posing potential secondary hazard to the environment. Trace amounts of over-oxidized NO3- and N2O were also detected. By 15N isotopes and urea analogues, we derived a nitrogen fate network, involving a NO2- formation pathway via OH--assisted C-N cleavage and two N2 formation pathways of intra- and inter-molecular coupling. Density functional theory (DFT) calculation confirmed that C-N cleavage is energetically more favorable. Inspired by the mechanism, a polyaniline coating strategy was developed to locally enrich urea for encouraging N2 production by 2-folds. These findings provide complementary insights into the nitrogen fate in water-energy nexus systems.
, Ke Shen, Bing Bai, Yu-Hsuan Liu
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111549

Abstract:
The outer surfaces of mycobacteria, including the organism that causes tuberculosis, are decorated with an array of immunomodulatory glycans. Among these are lipooligosaccharides (LOS), a class of molecules for which the function remains poorly understood. We describe the chemical synthesis of the glycan portion of a tridecasaccharide LOS (2) from the opportunistic pathogen Mycobacterium kansasii. The target contains a number of unusual structural motifs that complicate its assembly. This report describes the first syntheses related to M. kansasii LOSs and 2 is the most complex mycobacterial LOS glycan to be synthesized to date when considering size and number of unique monosaccharides and glycosidic linkages. These studies not only provide a roadmap for the preparation of additional members of this family of glycans, but also provides a valuable probe for use in structure–activity relationship investigations
Sarah N. Spisak, Zheng Zhou, Shuyang Liu, Qi Xu, Zheng Wei, Kenta Kato, Yasutomo Segawa, Kenichiro Itami, Andrey Yu. Rogachev,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110748

Abstract:
The stepwise chemical reduction of molecular warped nanographene (WNG) having a negatively curved π -surface and defined C 80 H 30 composition with Cs metal used as the reducing and complexing agent allowed the isolation of three different reduced states with one, two, and three electrons added to its π -conjugated system. This provided a unique series of contorted nanosized carbanions with increasing negative charge for in-depth structural analysis of consequences of controlled electron charging of non-planar nanographenes, using X-ray crystallographic and computational tools. The 3D molecular electrostatic potential (MEP) maps identified the negative charge localization at the central part of the WNG surface where selective coordination of Cs + ions has been confirmed crystallographically. In-depth theoretical investigation revealed a complex response of WNG to the stepwise electron acquisition. The extended and contorted π -surface of WNG undergoes subtle swinging distortions that are accompanied by notable changes in the electronic structure and site-dependent aromaticity of the resulting nanosized carbanions.
Shu Sakamoto, Trevor W. Butcher, Jonathan L Yang,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111476

Abstract:
We report the palladium-catalyzed gem -difluoroallylation of aryl halides and pseudo halides with 3,3-difluoroallyl boronates in high yield with high regioselectivity, and we report the preparation of the 3,3-difluoroallyl boronate reactants by a copper-catalyzed defluorinative borylation of inexpensive gaseous 3,3,3-trifluoropropene with bis(pinacolato)diboron. The gem -difluoroallylation of aryl and heteroaryl bromides proceeds with low catalyst loading (0.1 mol% [Pd]) and tolerates a wide range of functional groups, including primary alcohols, secondary amines, ethers, ketones, esters, amides, aldehydes, nitriles, halides, and nitro groups. This protocol extends to aryl iodides, chlorides, and triflates, as well as substituted difluoroallyl boronates, providing a versatile synthesis of gem -difluoroallyl arenes that we show to be valuable intermediates to a series of fluorinated building blocks.
Sara Szymkuc, Tomasz Badowski,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111540

Abstract:
In terms of molecules and specific reaction examples reported in the literature, organic chemistry features an impressive, exponential growth. However, new reaction classes/types that fuel this growth are being discovered at a much slower and only linear (or even sublinear) rate. In effect, the proportion of newly discovered reaction types to all reactions being performed keeps decreasing, suggesting that synthetic chemistry becomes more reliant on reusing the well-known methods. On the brighter side, the newly discovered chemistries are more complex than decades ago, and allow for the rapid construction of complex scaffolds in fewer numbers of steps. In this paper, we study these and other trends in the function of time, reaction-type “popularity” and complexity based on the algorithm that extracts generalized reaction class templates. These analyses are useful in the context of computer-assisted synthesis, machine learning (to estimate the numbers of models with sufficient reaction statistics), and also for identifying erroneous entries in reaction databases.
, Yang Yao, Sara Catalini, Bence Kutus, Johannes Hunger, Paolo Foggi
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110975

Abstract:
We investigate the static and dynamic states of water network during the phase transitions from double gyroid (Ia3d) to double diamond (Pn m) bicontinuous cubic phases and from the latter to the reverse hexagonal (HII) phase in monolinolein based lipidic mesophases by combining FTIR and broadband dielectric spectroscopy (BDS). In both cubic(s) and HII phase, two dynamically different fractions of water are detected and attributed to the bound and the interstitial free water. The dynamics of the two water fractions are all slower than bulk water due to the hydrogen-bonds between water molecules and the lipid’s polar headgroups and to nanoconfinement. Both FTIR and BDS results suggest that a larger fraction of water is bonded to the headgroup of lipids in HII phase at higher temperature than in cubic phase at lower temperature via H-bonds, which is different from the common expectation that the H-bonds should decrease with increase of temperature. These findings are rationalized by considering the topological ratio of interface/volume of the two mesophases.
Doruk Ergocmen,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111619

Abstract:
We describe a facile synthesis of the cyapho-cyanamide salt [Na(18-crown-6)][N(CN)(CP)] from reaction of [Na(18-crown-6)][PH 2 ] (18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane) with dimethyl N -cyanocarbonimidate, (MeO) 2 C=N(CN). The reaction proceeds with elimination of two equivalents of methanol. Careful tuning of the reaction conditions allowed for the isolation and characterization of the N -cyano(carboximidate)phosphide intermediate [HP{C(OMe)N(CN)}] − . Due to the adverse effects of methanol in these reaction mixtures, a bulk scale synthesis of [Na(18-crown-6)][N(CN)(CP)] could be achieved by addition of a base (LiHMDS) to neutralize the resulting alcohol. Further reactivity studies of this anion reveal that functionalization at the phosphorus atom is viable to yield a new family of cyanide-functionalised phosphorus heterocycles.
Lili Teng, Xiaoyu Han, Yongchao Liu, Chang Lu, Baoli Yin, Shuangyan Huan, Xia Yin, Xiao-Bing Zhang,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110427

Abstract:
Nanozymes with intrinsic enzyme-like characteristics have attracted enormous research interest in biological application, due to their higher catalytic stability and activity than many natural enzymes. However, there is still a lack of facile approach for real-time evaluating the catalytic activity of nanozymes in living system, which limits their application in precise treatment of disease. Herein, we develop a novel manganese-semiconducting polymer-based nanozyme (MSPN) with oxidase-like activity for dynamically reporting the catalytic activity of itself in acid-induced cancer therapy via ratiometric near-infrared fluorescence (NIRF)-photoacoustic (PA) molecular imaging. Notably, MSPN possess oxidase-like activity in tumor microenvironment, owing to the mixed-valent MnOx nanoparticles ((Mn II ) 1 (Mn III ) 1.56 (Mn IV ) 1.4 O 6.14 ), which can effectively kill cancer cells. Because the semiconducting polymer (PFODBT) is conjugated with oxidase-responsive molecule (ORM) via amide bond, the catalyitic activity of nanozyme can be correlated with the ratiometric sginals of NIRF (FL 695 /FL 825 ) and PA (PA 680 /PA 780 ). Therefore, our integrated catalyitic and imaging platform represents an innovative strategy that can not only achieve effective catalyitic activity in vivo, but also be used to real-time monitor the nanozyme acitivity itself, which may provide new ideas for predicating anticancer effiecncy of nanozymes in biological condition.
, Lin Chen, Na Li, Meiqi Zhang, Mingming Sun, Jiaxuan Bian, Zhengcunxiao Li, Jiayu Wang, Fei Li, Xiaomeng Shi, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108961

Abstract:
Mammalian cell nuclei contain copper, and cancer cells are known to accumulate aberrantly high copper levels, yet the mechanisms underlying nuclear accumulation and copper’s broader functional significance remain poorly understood. Here, by combining APEX2-based proximity labeling focused on the copper chaperone Atox1 with mass spectrometry we identified a previously unrecognized nuclear copper binding protein, Cysteine-rich protein 2 (CRIP2), that interacts with Atox1 in the nucleus. We show that Atox1 transfers copper to CRIP2, which induces a change in CRIP2’s secondary structure that ultimately promotes its ubiquitin-mediated proteasomal degradation. Finally, we demonstrate that depletion of CRIP2—as well as copper-induced CRIP2 degradation—elevates ROS levels and activates autophagy in H1299 cells. Thus, our study establishes that CRIP2 as an autophagic suppressor protein and implicates CRIP2-mediated copper metabolism in the activation of autophagy in cancer cells.
, Ruo-Chen Guo, Xue-Hao Zhang, Peng-Sheng Fan, Ben-Li Song, Zhi-Xiang Li, Zhong-Yu Duan, Zeng-Ying Qiao
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111839

Abstract:
Therapeutic peptides have been widely concerned because of their good biocompatibility, but their efficacy is limited by the inability to penetrate cell membranes, which is a key bottleneck in peptide drugs delivery. Herein, an in vivo self-assembly strategy is developed to induce phase separation of cell membrane that improves the peptide drugs internalization and anticancer efficacy. A phosphopeptide KYp is synthesized, containing an anticancer peptide [KLAKLAK] 2 (K) and a responsive moiety phosphorylated Y (Yp). After interacting with alkaline phosphatase (ALP) on the cell membrane, KYp can be dephosphorylated and self-assembles in situ , which induces the aggregation of ALP and the protein-lipid phase separation on the cell membrane. ALP is involved in the assembly of peptides, forming the large aggregates and entering cells, which leads to the enhanced permeability of cell membrane. Consequently, the peptide drugs internalization is ~2-fold enhanced compared to non-responsive peptide nanoparticle, and IC 50 value of KYp is approximately ~5 times lower than that of free peptide. Finally, the tumor of mice treated with KYp is suppressed effectively, showing the negligible side effect in vivo . Therefore, the in vivo self-assembly induced phase separation on the cell membrane promises a new strategy to improve the drug delivery efficacy in cancer therapy.
Laura Macdougall, Maria Perez-Madrigal, Joshua Shaw, Joshua Worch, Stephen Richardson, Christopher Sammon,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202107161

Abstract:
The stereochemistry of polymers has a profound impact on their mechanical properties. While this has been observed in thermoplastics, studies on how stereochemistry affects the bulk properties of swollen networks, such as hydrogels, are limited. Typically, changing the stiffness of a hydrogel is achieved at the cost of changing another parameter, that in turn affects the physical properties of the material and ultimately influences the cellular response. Herein, we report that by manipulating the stereochemistry of a double bond, formed in situ during gelation, materials with diverse mechanical properties but comparable physical properties can be obtained. Click-hydrogels that possess a high % trans content are stiffer than their high % cis analogues by almost a factor of 3. Human mesenchymal stem cells acted as a substrate stiffness cell reporter demonstrating the potential of these platforms to study mechanotransduction without the influence of other external factors.
Yangdao Wei, Zhiqing Yang, Chengli Zong, Buhua Wang, Xiaolin Ge, Xiao Tan, Xin Liu, Zhenzhen Tao, Peng Wang, Chunxin Ma, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110384

Abstract:
As a CRISPR-Cas system (clustered regularly interspaced short palindromic repeats and CRISPR associated proteins), Cas14a1 can cis / trans cleave single-stranded DNA (ssDNA). Here, we discover an un-reported capacity of Cas14a1, RNA can trigger the trans ssDNA cleavage. This Cas14a1-based RNA-activated detection platform ( A mplification, T ranscription, C as 14a1-based RNA -activated trans ssDNA cleavage, ATC as -RNA ) has an outstanding specificity for the detection of target RNAs with point mutation resolution, which is better than that of the Cas14a1-based ssDNA-activation. Using ATCas-RNA via a fluorophore quencher-labeled ssDNA reporter (FQ), we were able to detect 1 aM pathogenic nucleic acid within 1 h, and achieve 100% accuracy with 25 milk samples. This platform can serve as a new tool for high efficiency nucleic acid diagnostics. Importantly, this work can expand our understanding of Cas14a1 and inspire further mechanisms and applications of Class-2 Cas systems.
Zhaoyang Chen, Huan Niu, Jie Ding, Heng Liu, Pei-Hsuan Chen, Yi-Hsuan Lu, Ying-Rui Lu, Wenbin Zuo, Lei Han, Yuzheng Guo, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110243

Abstract:
Heteroatom doped atomically dispersed Fe 1 -NC catalysts have been found to show excellent activity toward oxygen reduction reaction (ORR). However, the origin of the enhanced activity is still controversial because the structure-function relationship governing the enhancement remains elusive. Herein, sulfur(S)-doped Fe 1 -NC catalyst was obtained as a model, which displays a superior activity for ORR towards the traditional Fe-NC materials. 57 Fe Mössbauer spectroscopy and electron paramagnetic resonance spectroscopy revealed that incorporation of S in the second coordination sphere of Fe 1 -NC can induce the transition of spin polarization configuration. Operando 57 Fe Mössbauer spectra definitively identified the low spin single-Fe 3+ -atom of C-FeN 4 -S moiety as the active site for ORR. Moreover, DFT calculations unveiled that lower spin state of the Fe center after the S doping promotes OH* desorption process. This work elucidates the underlying mechanisms towards S doping for enhancing ORR activity, and paves a way to investigate the function of broader heteroatom doped Fe 1 -NC catalysts to offer a general guideline for spin-state-determined ORR.
, Xiao-Long Zhang, Xiaozhi Su, Ya-Rong Zheng, Shao-Jin Hu, Lei Shi, Fei-Yue Gao, Peng-Peng Yang, Zhuang-Zhuang Niu, Zhi-Zheng Wu, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111075

Abstract:
Electrosynthesis of hydrogen peroxide (H2O2) in the acidic environment could largely prevent its decomposition to water, but efficient catalysts that constitute entirely earth-abundant elements are lacking. Here we report the experimental demonstration of narrowing the interlayer gap of metallic cobalt diselenide (CoSe2), which creates high-performance catalyst to selectively drive two-electron oxygen reduction toward H2O2 in an acidic electrolyte. The enhancement of the interlayer coupling between CoSe2 atomic layers offers a favorable surface electronic structure that weakens the critical *OOH adsorption, promoting the energetics for H2O2 production. Consequently, on the strongly coupled CoSe2 catalyst, we achieved Faradaic efficiency of 96.7%, current density of 50.04 milliamperes per square centimeter, and product rate of 30.60 mg cm-2 h-1. Moreover, this catalyst shows no sign of degradation when operating at -63 milliamperes per square centimeter over 100 hours
Junnan Hao, Libei Yuan, Bernt Johannessen, Yilong Zhu, Yan Jiao, Chao Ye, Fangxi Xie,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111398

Abstract:
Aqueous Zn-ion batteries (ZIBs) are regarded as alternatives to Li-ion batteries benefiting from both improved safety and environmental impact in addition to being easy to manufacture at scale. The widespread application of ZIBs, however, is compromised by the lack of high-performance cathodes. Currently, only the intercalation mechanism is widely reported in aqueous ZIBs, which significantly limits cathode options. Beyond Zn-ion intercalation, we comprehensively study the conversion mechanism for Zn-ion storage and its diffusion pathway in a CuI cathode, indicating that CuI occurs a direct conversion reaction without Zn-ion intercalation due to the high energy barrier for Zn-ion intercalation and migration. Importantly, this direct conversion reaction mechanism can be readily generalized to other high-capacity cathodes, such as Cu2S (336.7 mA h g-1) and Cu2O (374.5 mA h g-1), indicating its practical universality. Our work enriches the Zn-ion storage mechanism and significantly broadens the cathode horizons towards next-generation ZIBs.
Yongqiang Zhang, Haoqiang Song, Lu Wang, Jingkun Yu, Boyang Wang, Yongsheng Hu, Shuang-Quan Zang, Bai Yang,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111285

Abstract:
Miniaturized solid-state lasers with a single longitudinal mode are vital for various photonic applications. Here we prepare red-emissive carbon dots (CDs) with a photoluminescence quantum yield (PLQY) of 65.5% by combining graphitic nitrogen doping and surface modification. High-concentration doping alters the CDs’ emission from blue to red, while the electron-donating groups and polymer coating on their surfaces improve the PLQY and photostability. The CDs exhibit excellent stimulated emission characteristics, with a low threshold of amplified spontaneous emission (ASE) and long gain lifetime. A planar microcavity with only one resonant mode, which fitted with the CDs’ ASE peak, was constructed. Combining the CDs and microcavity produced a solid-state laser with a single longitudinal mode, a linewidth of 0.14 nm and a signal-to-noise ratio of 14.8 dB. Our results will aid the development of colorful solid-state micro/nano lasers with potential use in practical photonics.
Qiyou Wang, Kang Liu, Junwei Fu, Chao Cai, HuangJingwei Li, Yan Long, Shanyong Chen, Bao Liu, Hongmei Li, Wenzhang Li, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109329

Abstract:
Atomically dispersed transition metal sites have been extensively studied for CO 2 electroredution reaction (CO 2 RR) to CO due to their robust CO 2 activation ability. However, the strong hybridization between directionally localized d orbits and CO vastly limits CO desorption and thus the activities of atomically d ispersed transition metal sites. In contrast, s-block metal sites possess nondirectional ly delocalized 3s orbits and hence weak CO adsorption ability, providing a promising way to solve the suffered CO desorption issue. Herein , we constructed atomically dispersed magnesium atoms embedded in graphitic carbon nitride ( Mg-C 3 N 4 ) through a facile heat treatment for CO 2 RR . Theoretical calculations show that the CO desorption on Mg sites is easier than that on Fe and Co sites. This theoretical prediction is demonstrated by experimental CO temperature program desorption and in-situ attenuated total reflection infrared spectroscopy. As a result, Mg-C 3 N 4 exhibits a high turnover frequency of ~ 18,000 per hour in H-cell and a large current density of -300 mA/cm 2 in flow cell , under a high CO Faradaic efficiency ≥90% in KHCO 3 electrolyte . This work sheds a new light on s-block metal sites for efficient CO 2 RR to CO.
, Qing Chang, Fangfang Wang, Wenxin Xu, Aifei Wang, You Liu, Juangan Wang, Yikai Yun, Song Gao, Kang Xiao, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202112074

Abstract:
Lead halide perovskites always emerge complex interactions among different elemental ions, which lead to multiple intrinsic imperfections. Elemental defects, such as amine, Pb, and I vacancies at A-, B-, and X-sites, are main issues to deteriorate perovskite solar cells (PSCs). Unfortunately, most previous passivators can only temporarily fix partial inactive vacancies as sacrificial agents. Herein, we propose a recovery agent - ferrocene (Fc), which can form a one-dimensional perovskite with adequate steric cavities and suitable dissociation energy to recover all elemental defects back to active light-harvesting perovskites, and regenerate Fc itself meanwhile. Based on this perpetual chain-reaction cycle, corresponding PSCs maintain >10,000-hour lifetime in inert condition and >1,000-hour durabilities under various extreme environments, including continuous 85ºC heating, 50% relative humidity wetting, and 1-sun light soaking.
Arighna Sarkar,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202107481

Abstract:
This article highlights recent pioneering work by Günther et al. towards the discovery of potential repurposed antiviral compounds (peptidomimetic and non-peptidic) against the SARS-CoV-2 main protease (Mpro). The antiviral activity of the most potent drugs is discussed along with their binding mode to Mpro as observed through X-ray crystallographic screening.
, Yi Ding, Samir K. Sakar, Mohd Nazish, Daniel Lüert, Paul Niklas Ruth, Christina Legendre, Shahila Muhammed, Regine Herbst- Irmer, Pattiyil Parameswaran, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110456

Abstract:
Herein, we report the stabilization of nitrene reagents as the source of a nitrogen atom to synthesize nitrogen incorporated R 1 LSi-N←SiLR 2 ( 1 ) [L= PhC(N t Bu) 2 ; R 1 = NTMS 2 , R 2 = NTMS]. Compound 1 is synthesized by reacting LSi(I)–Si(I)L with 3.1 equivalents of Me 3 SiN 3 at low temperature to afford a triene-like structural framework. Whereas the reaction of the LSi(I)–Si(I)L with 2.1 equivalents of Me 3 SiN 3 at room temperature produced silaimine 2 with a central four-membered Si 2 N 2 ring which is accompanied by a silylene LSi and a cleaved silylene fragment. 1 further reacts with AgOTf at room temperature to yield compound 3 which shows coordination of nitrene to silver with the triflate salt. The compounds 1 and 2 were fully characterized by NMR, mass spectrometry, and X-ray crystallographic analysis. The quantum mechanical calculations reveal that compounds 1 and 2 have dicoordinated monovalent N atoms having two active lone pairs of electrons. These lone pairs are stabilized by hyperconjugative interactions.
Yanrong He, Shu Zhang, Hari Bisoyi, Jinghui Qiao, Hong Chen, Jingjing Gao, Jinbao Guo,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111344

Abstract:
Two novel light-driven chiral fluorescent molecular switches, (R,S,R)-switch 1 and (R,S,R)-switch 2 , are prepared by means of hydrogen-bonded (H-bonded) assembly of a photoresponsive (S) chiral fluorescent molecule respectively with a cyano substitution at different positions as an H-bond acceptor and an opposite (R) chiral molecule as an H-bond donor. The resulting two switches exhibit tunable and reversible Z/E photoisomerization irradiated with 450 nm blue and 365 nm UV light. When doped into an achiral liquid crystal, both switches are found to be able to form a CPL tunable luminescent helical superstructure. Interestingly, in contrast to the tunable CPL characteristics of the system incorporating switch 2, exposure of the system incorporating switch 1 to 365 nm and 450 nm radiation can lead to controllable different photostationary CPL behavior, including switching-off and polarization inversion. In addition, optical information coding was demonstrated using the system containing switch 1.
, Jing Zhang, Mingchen Xie, Ying Xin, Chunmiao Han, Linghai Xie, Mingdong Yi
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111320

Abstract:
Realizing the differentiated functions of organic-inorganic hybrids is the basis of constructing single-molecule semiconductor elements as a formidable challenge. Herein, we report a feasible molecular design of the binuclear clusters featuring the n-p-n heterojunction of biligand-sandwiched inorganic units, which can be used as the effective charge trapper in ambipolar transistor memories with the large memory windows and the energy-saving operation. We find that the hole confinement on the p-type inorganic units is enhanced by spatial electronic anisotropy provided by the peripheral n-type organic phosphine ligands. The steric hindrance of the coordination sites, the insulating effect of the carbon-phosphorous single bonds and the parallel dual-ligand coordination mode jointly elongate the interunit distances to nanometer scale and restrain the intramolecular electronic communications, leading to the tunable and reliable charge trapping. Our results show that the spatial effect is crucial to further amplifying the electronic differences between organic and inorganic units for function enhancement. The combination of spatial and electronic effects will be useful in developing single-molecule semiconductor elements.
Tianbiao Zeng, Xingang Liu, Wenbin Kang, Hanna He, Jihai Zhang, Xiaolong Li, Chuhong Zhang
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111498

Abstract:
As a nascent anode material for lithium-ion batteries (LIBs) , layered germanium phosphide (GeP) boasts excellent potential due to its high capacity , decent conductivity, and excellent theoretically calculated Li + diffusion coefficient. However, in reality, GeP usually suffers from relatively slow Li + diffusion and poor cycling stability associated with its stiff bulky structure as synthesized using conventional mixing-sintering method, in which the predicted quickest electron-ion transport pathways tend to be concealed. Herein, for the first time, we propose an in-situ template method to directionally induce the construction of GeP nanobar (GeP-nb) coral s with an adjustable aspect ratio . The GeP nanobars grown onto conductive matrix with high aspect ratio expose more quickest electron-ion transportation facets for fast reaction dynamics, which not only is the first verification of the theoretical prediction, but also reveals the underlying mechanism of crystal orientation optimization on the electrochemical behavior of GeP-based materials. Besides, the customized GeP-nb electrode delivers a self-healable homeostatic behavior by reversibly stabilizing GeP crystalline structure through multi-phase reactions to maintain structural integrity and cycling stability (850 mAh g -1 at 1 A g -1 after 500 cycles). As a result, the GeP-nb presents the highest Li + diffusion coefficient (6.21×10 -11 cm 2 s -1 ) among all the Ge-based anode materials studied so far, rendering an excellent rate performance (620 mAh g -1 at 5 A g -1 ) as a LIBs anode. This unique in-situ structural regulation strategy for improved ion diffusion points to a valuable roadmap for the rational design of novel electrode materials for futuristic high energy density batteries.
Florian Baffie, Georgios Patias, Ataulla Shegiwal, Fabrice Brunel, Vincent Monteil, Ludmilla Verrieux, Lionel Perrin, David M. Haddleton,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108996

Abstract:
Two scalable polymerization methods are used in combination for the synthesis of ethylene and methacrylate block copolymers. ω-Unsaturated methacrylic oligomers (MMA n ) produced by catalytic chain transfer (co)polymerisation (CCTP) of methyl methacrylate (MMA) and methacrylic acid (MAA) are used as reagents in the radical polymerization of ethylene (E) in dimethyl carbonate solvent under relatively mild conditions (80 bar, 70°C). Kinetic measurements and analyses of the produced copolymers by size exclusion chromatography (SEC) and a combination of nuclear magnetic resonance (NMR) techniques indicate that MMA n is involved in a degradative chain transfer process resulting in the formation of (MMA) n - b -PE block copolymers. Molecular modelling performed by DFT supports the overall reactivity scheme and observed selectivities. The effect of MMA n molar mass and composition is also studied. The block copolymers were characterised by differential scanning calorimetry (DSC) and their bulk behaviour studied by SAXS/WAXS analysis
Guitao Feng, Wenliang Tan, Safakath Karuthedath, Cheng Li, Xuechen Jiao, Amelia C. Y. Liu, Hariprasad Venugopal, Zheng Tang, Long Ye, Frédéric Laquai, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111192

Abstract:
Highly-crystalline conjugated polymers are important for microstructure analysis and charge transport in organic electronics. In this work, we have developed a series of highly-crystalline double-cable conjugated polymers for application in single-component organic solar cells (SCOSCs). These polymers contain conjugated backbones as electron donor and pendant perylene bisimide units (PBIs) as electron acceptor. PBIs are connected to the backbone via alkyl units varying from hexyl (C6H12) to eicosyl (C20H40) as flexible linkers. The highly-crystalline nature of these materials allows us to systematically study the effect of the length of the alkyl linkers on the nanostructure and photovoltaic performance. In particular, we find that for double-cable polymers with short linkers, the PBIs tend to stack in a head-to-head fashion, resulting in large d-spacing (e.g. 64 Å for the polymer P12 with C12H24 linker) along the lamellar stacking direction. When the length of the linker groups is longer than a certain length, the PBIs instead adopt a more ordered packing likely via H-aggregation, resulting in short d-spacings (e.g. 50 Å for the polymer P16 with C16H32 linker). Evidence for this transition is provided by X-ray diffraction measurements along with cryo-transmission electron microscopy measurements, where different packing motifs of the PBI units are clearly imaged. The different packing facilitated by longer linker groups is associated with improved exciton separation and charge transport, resulting in enhanced efficiencies of SCOSCs based on the polymer P16. The findings in this work demonstrate that double-cable conjugated polymers can be an important family of highly-crystalline conjugated polymers. Furthermore, this work demonstrates how the precise molecular packing of the acceptor units influences the photovoltaic performance of SCOSCs.
Congxu Wang, Hualei Zhang, Wenjia Luo, Tian Sun,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109851

Abstract:
Ultrathin nanosheets demonstrate great potential for photocatalytic applications, however, suffer from enlarged bandgap and narrowed visible-light-responsive range due to the quantum confinement effect. Herein, we report a novel redox strategy for efficient preparation of ultrathin crystalline amide-functionalized covalent-triazine-framework nanosheets (CTF NSs) with enhanced visible light absorption for the first time. The obtained CTF NSs exhibited remarkable photocatalytic hydrogen (512.3 μmol h -1 ) and oxygen (12.37 μmol h -1 ) evolution rates, 17 and 23 times higher than that of pristine bulk CTF, respectively. Moreover, the photocatalytic overall water splitting could also be achieved by the CTF NSs with efficient stoichiometric H 2 (5.13 μmol h -1 ) and O 2 (2.53 μmol h -1 ) evolution rates under visible light irradiation, which is superior to previous CTFs/covalent-organic frameworks-based photocatalytic materials. Experimental and theoretical analysis revealed that introduction of a small amount of amide groups as electron donor in the CTF NSs could optimize its band structure and improve its visible-light absorption, hydrophilicity and carrier separation efficiency, thus resulting in significantly enhanced photocatalytic performance. Additionally, the well-dispersed CTF NSs could be easily casted onto a support as a thin film device and demonstrate excellent photocatalytic activity (25.7 mmol h -1 m -2 for hydrogen evolution), which has rarely been achieved before.
Aishan Deng, Xintian Shen, Zhen Wan, Yanhong Li, Shuyue Pang, Xiao He, Jürgen Caro,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110828

Abstract:
Metal-organic framework membranes are usually prepared by in-situ or secondary growth in a solution/hydrogel. The use of organic solvents may cause safety and environmental problems, and also produce solvent-induced defects. In this work, highly oriented and permselective ZIF-95 membranes are prepared for the first time via a solvent-free secondary growth method. The solvent-free growth is not only helpful to control the membrane microstructure and thickness, but also to reduce the intercrystalline defects. In case of solvent-free growth, a perfectly oriented structure leads to an outstanding reduction of intercrystalline defects and transport resistances. For the separation of equimolar binary gas mixtures by using the highly oriented ZIF-95 membrane at
Kalyan Biswas, , Kun Xu, Ji Ma, Ana Sánchez-Grande, Pingo Mutombo, Aurelio Gallardo-Caparrós, Koen Lauwaet, Benjamin Mallada, Bruno de la Torre, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111863

Abstract:
The atomically precise control over the size, shape and structure of nanographenes (NGs) or the introduction of heteroatom dopants into their sp2-carbon lattice confer them valuable electronic, optical and magnetic properties. Herein, we report on the design and synthesis of a hexabenzocoronene derivative embedded with graphitic nitrogen in its honeycomb lattice, achieved via on-surface assisted cyclodehydrogenation on the Au(111) surface. Combined scanning tunneling microscopy/spectroscopy and non-contact atomic force microscopy investigations unveil the chemical and electronic structures of the obtained dicationic NG. Kelvin probe force microscopy measurements reveal a considerable variation of the local contact potential difference toward lower values with respect to the gold surface, indicative of its positive net charge. Altogether, we introduce the concept of cationic nitrogen doping of NGs on surfaces, opening new avenues for the design of novel carbon nanostructures.
Anni Shi, Terry A. Villarreal, Anamika Singh, Tyler R. Hayes, Tyson C. Davis, Jacob T. Brooks,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110517

Abstract:
Lamellar phases of alkyldiacetylenes, in which the alkyl chains lie parallel to the substrate, represent a straightforward means for scalable 1-nm-resolution interfacial patterning. This capability has the potential for substantial impacts in nanoscale electronics, energy conversion, and biomaterials design. Polymerization is required to set the 1-nm functional patterns embedded in the monolayer, making it important to understand structure–function relationships for these on-surface reactions. Polymerization can be observed for certain monomers at the single-polymer scale using scanning probe microscopy. However, substantial restrictions on the systems that can be effectively characterized have limited utility. Here, using a new multi-scale approach, we identify a large, previously unreported difference in polymerization efficiency between the two most widely used commercial diynoic acids. We further identify a core design principle for maximizing polymerization efficiency in these on-surface reactions, generating a new monomer that also exhibits enhanced polymerization efficiency.
Hui Li, Peiping Yu, Renbo Lei, Feipeng Yang, Pen Wen, Xiao Ma, Guosong Zeng, Jinghua Guo, Francesca M. Toma, Yejun Qiu, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109600

Abstract:
Catalysts based on Cu nanocrystals (NCs) for electrochemical CO 2 -to-C 2+ conversion with high activity have been a subject of considerable interest, but poor stability and low selectivity for a single C 2+ product remain obstacles for realizing sustainable carbon-neutral cycles. Here, we used the facet-selective atomic layer deposition (FS-ALD) technique to selectively cover the (111) surface of Cu NCs with ultrathin Al 2 O 3 to increase the exposed facet ratio of (100)/(111), resulting in a faradaic efficiency ratio of C 2 H 4 /CH 4 for overcoated Cu NCs 22 times higher than that for pure Cu NCs. Peak performance of the overcoated catalyst (Cu NCs/Al 2 O 3 -10C) reaches a C 2 H 4 faradaic efficiency of 60.4% at a current density of 300 mA cm -2 in 5 M KOH electrolyte, when using a gas diffusion electrode flow cell. Moreover, the Al 2 O 3 overcoating effectively suppresses the dynamic mobility and the aggregation of Cu NCs, which explains the negligible activity loss and selectivity degradations of Cu NCs/Al 2 O 3 -10C shown in stability tests.
, Kapil Upadhyaya, Yagya A Subedi
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110212

Abstract:
Low-temperature NMR studies with a 4- C -methyl-4- O -benzoyl galactopyranosyl donor enable for the first time the observation and characterization of a bridged bicyclic dioxacarbenium ion arising from participation by a distal ester. Variable temperature NMR studies reveal this bridged ion to decompose at temperatures above ~-30 °C. In the absence of the methyl group, the formation of a bicyclic ion is not observed. It is concluded that participation by typical secondary distal esters in glycosylation reactions is disfavored in the ground state conformation of the ester from which it is stereoelectronically impossible. Methylation converts the secondary ester to a conformationally more labile tertiary, removes this barrier, and renders participation more favorable. Nevertheless, the minor changes in selectivity in model glycosylation reactions on going from the secondary to the tertiary esters at both low and room temperature argue against distal group participation being a major stereodirecting factor even for the tertiary system.
, Dong Wang, Peifeng Liu
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110666

Abstract:
DNA is a true polymer that stores the genetic information for an organism. With its amazing biological and polymeric characters, DNA has been regarded as a universal building block for the construction of diverse materials for real-world applications. Through various approaches including ligation, polymerization, chemical crosslinking, and physical cross-linking, both pure and hybrid DNA gels have been developed as generic materials. This minireview discusses the recent advances in the construction strategies of DNA-based networks without considering any of DNA’s genetic properties. In addition, this minireview highlights the biomedical and non-biomedical applications of DNA as generic materials. With the superb molecular recognition, self-assembly, and responsiveness, a mushrooming number of DNA materials with various properties would be developed for general utilization.
, Xu-Zhe Wang, Shu-Lin Meng, Jia-Yi Chen, Hai-Xu Wang, Yang Wang, Shuai Zhou, Xu-Bing Li, Rong-Zhen Liao, Chen-Ho Tung
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202107386

Abstract:
A bis(pyridyl)amine-bipyridine-iron(II) framework (Fe(BPAbipy)) of complexes 1-3 is reported to shed light on the multistep nature of CO 2 reduction. Herein, photocatalytic conversion of CO 2 to CO even at low CO 2 concentration (1%), together with detailed mechanistic study and DFT calculations, reveal that 1 first undergoes two sequential one-electron transfer affording an intermediate with electron density on both Fe and ligand for CO 2 binding over proton. The following 2H + -assisted Fe-CO formation is rate-determining for selective CO 2 -to-CO reduction. A pendant, proton-shuttling α-OH group ( 2 ) initiates PCET for predominant H 2 evolution, while an α-OMe group ( 3 ) cancels the selectivity control for either CO or H 2 . The near-unity selectivity of 1 and 2 enables self-sorting syngas production at flexible CO/H 2 ratios. The unprecedented results from one kind of molecular catalyst skeleton encourage insight into the beauty of advanced multi-electron and multi-proton transfer processes for robust CO 2 RR by photocatalysis.
Xiangyun Xiao, Chao Chen, Yehao Zhang, Huihui Kong, Rong An, Suang Li, Wei Liu,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110187

Abstract:
Quartz crystal microbalance (QCM) is one of the powerful tools for the studies of molecular recognition and chiral discrimination. Its efficiency mainly relies on the design of the functional sensitive layer on the electrode surface. However, the organic sensitive layer may easily cause dissipation of oscillation or detachment and weaken the signal transfer during the molecular recognition processes. In this work, we reveal for the first time that the bare metal surface without the organic selector layer has the capability for chiral recognition in the QCM system. During the adsorption of various chiral amino acids, relatively higher selectivity of D-enantiomers on gold (Au) surface was shown by the QCM detection. Based on analyses of the surface crystalline structure and density functional theory calculations, we demonstrate that the chiral nature of Au surface plays an important role in the selective binding of specific D-amino acids. These results may open new insights on chiral detection by QCM system. It will also promote the construction of novel chiral sensing systems with both efficient detection and separation capability.
Sijie Xie, Wouter Monnens, Kai Wan, Wei Zhang, Wei Guo, Maowen Xu, Ivo F.J. Vankelecom, Xuan Zhang, Jan Fransaer
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108485

Abstract:
Metal-organic framework (MOF) films can be made by cathodic electrodeposition, where a Brønsted base is formed electrochemically which deprotonates the MOF linkers that are present in solution as undissociated/partially dissociated weak acids. However, the co-deposition of metal and the narrow range of possible metal nodes limit the scope of this method. In this work, we propose the use of hydrogen peroxide (hydrogen peroxide assisted cathodic deposition or HPACD), to overcome these limitations. Electrochemical measurements indicate that in DMF, hydrogen peroxide is reduced to superoxide anions that deprotonate the carboxylic ligands. This single-electron reduction happens at much higher potentials than all previous reported methods. This prevents the co-deposition of metal and extends the range of possible metal nodes. Various pure MOF films (HKUST-1, MIL-53(Fe) and MOF-5) were prepared via this approach. HPACD was also used for the preparation of patterned MOF films and of flexible Cu-BTC coated paper membranes which rejects 99.1% of Rose Bengal from water with a permeance of 8.4 L m -2 h -1 bar -1 .
Xiaoxuan Su, Wenxiao Ma, Di Feng, Boyang Cheng, Qian Wang, Zefeng Guo, Dr. Demin Zhou,
Angewandte Chemie International Edition, Volume 60; https://doi.org/10.1002/anie.202184061

Abstract:
SARS-CoV-2 In their Communication on page 21662, Xinjing Tang et al. report the efficient inhibition of SARS-CoV-2 using chimeric antisense oligonucleotides through RNase L activation.
Fabian H. Sobotta, Maren T. Kuchenbrod, Franka V. Gruschwitz, Grit Festag, Peter Bellstedt, Stephanie Hoeppener,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108928

Abstract:
The confinement in and the selective release from vesicular structures is an elementary part of biological transport processes and highly attractive for drug delivery systems. Reactive polymersomes represent a versatile artificial cargo carrier system, which can facilitate an immediate release in response to a specific stimulus. The herein presented oxidation-sensitive polymersomes feature a time delayed release mechanism in an oxidative environment, which can be precisely adjusted by either tuning the membrane thickness or partial pre-oxidation. These polymeric vesicles are conveniently prepared by polymerization-induced self-assembly (PISA) allowing the straightforward and effective in situ encapsulation of cargo molecules, as exemplarily shown for fluorescence dyes and functional enzymes. Detailed kinetic studies revealed a critical degree of oxidation causing the destabilization of the membrane, while no release of the cargo is observed beforehand. The encapsulation of glucose oxidase transforms these polymersomes directly into glucose-sensitive vesicles, as small molecules including sugars can passively penetrate their membrane. Considering the ease of preparation, the presented polymersomes represent a versatile platform for the confinement and a burst release of cargo molecules after a precisely adjustable time span in the presence of specific triggers, such as hydrogen peroxide or glucose.
Liangbo Hu, Ying Li, Xinhui Lin, Yucheng Huo, Hongyue Zhang,
Angewandte Chemie International Edition, Volume 60; https://doi.org/10.1002/anie.202184062

Abstract:
Supramolecular Chemistry Structure-based programming of supramolecular assemblies in living cells for selective cancer cell inhibition is reported by Huaimin Wang et al. in their Research Article on page 21807.
, Vincent St-Onge, Sylviane Rochon, Jean-Christophe Daigle, Armand Soldera
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109709

Abstract:
The low conductivity of Na + electrolytes in solid polymer electrolytes (SPEs) curtails the development of Na polymer batteries. In this study, NaClO 4 (3-24 wt%, 90-9:1 O:Na) is dissolved in statistical copolymers of ethylene oxide (EO) and propylene oxide (PO) (0-20 mol%). Remarkably, the conductivity of these SPEs increases as the concentration of Na + decreases, thus departing from the usual Nernstian behaviour. Using a combination of calorimetric measurements and molecular dynamic simulations, this unusual phenomenon is attributed to the presence of physical cross-links generated by Na + . As a result, polymers containing a low salt concentration (3 wt%) display a drastically enhanced ionic conductivity (up to 0.2 10 -4 S/cm at 25°C), thus paving the way for the design of all-solid-state PEO-based sodium batteries operational at room temperature.
, Michael J. Gunther, Radoslav Z. Pavlović, Tyler J. Finnegan, Xiuze Wang
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110849

Abstract:
The precise positioning of functional groups about the inner space of abiotic hosts is a challenging task and of interest for developing more effective receptors and catalysts akin to those found in nature. To address it, we herein report a synthetic methodology for preparing basket-like cavitands comprising of three different aromatics as side arms with orthogonal esters at the rim for further functionalization. First, enantioenriched A (borochloronorbornene), B (iodobromonorbornene) and C (boronorbornene) building blocks were obtained by stereoselective syntheses. Second, consecutive A -to- B and then AB -to- C SuzukiMiyaura (SM) couplings were optimized to give enantioenriched ABC cavitand as the principal product. The robust synthetic protocol allowed us to prepare (a) enantioenriched basket with three benzene sides and each holding either t -Bu, Et or Me esters, (b) both enantiomers of so-called “spiral staircase” basket with benzene, naphthalene and anthracene groups surrounding the inner space and (c) photo-responsive basket bearing one anthracene and two benzene arms.
Sida Li, Chenyang Hu, Xin Cui, Liu Leo Liu,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202111978

Abstract:
An unprecedented and general hydroboration of alkenes with BX3(X = Br, Cl) as the boration reagent in the presence of iPr2NEt is reported. The addition of iPr2NEt not only suppresses alkene polymerization and haloboration side reactions but also provides an "H" source for hydroboration. More importantly, the site-fixed installation of a boryl group at the original position of the internal double-bond is readily achieved as compared with conventional transition-metal-catalyzed hydroboration processes. Further application to the synthesis of 1, n-diborylalkanes (n=3-10) is also demonstrated. Preliminary mechanistic studies reveal a major reaction pathway that involves radical species and operates through frustrated-Lewis-pair-type single-electron transfer mechanism.
Jianhua Yang, Jiapeng Zheng, Ruoqi Ai, Yunhe Lai, Tsz Him Chow, Lei Shao,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108487

Abstract:
Light-driven nanomotors have attracted much attention due to their potential applications. The movement of conventional nanomotors typically occurs in the solution phase, which limits their application fields. Utilizing visible light to drive nanomotors at the solid–liquid interface represents a grand challenge due to the large friction force between the nanomotor and the solid surface. Based on the attractive plasmon resonance of Au nanocrystals, for the first time, plasmon-enhanced Au nanocrystal-based nanomotors moving at the silicon–aqueous solution interface have been developed. Such nanomotors move with a clear trace engraved on the Si surface, representing an excellent and exceptional self-traced nanomotor system. In addition, the nanomotor trace on the Si surface also provides a unique and promising approach to the fabrication of nanoscale Si patterns, which is central to many applications, including microelectronics, sensing, information storage, and optoelectronics.
, Jia Qiao, Zi-Qi Song, Cheng Huang, Rui-Nan Ci, Zan Liu, Bin Chen, Chen-Ho Tung
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202109849

Abstract:
As one of the most ubiquitous bulk reagents available, the intrinsic chemical inertness of tetrahydrofuran (THF) makes direct and site-selective C(sp 3 )−H bond activation difficult, especially under redox neutral condition. Here, we demonstrate that semiconductor quantum dots (QDs) can activate α-C–H bond of THF via forming QDs/THF conjugates. Under visible light irradiation, the resultant alkoxyalkyl radical directly engages in radical cross-coupling with α-amino radical from amino C–H bonds or radical addition with alkene or phenylacetylene, respectively. In contrast to stoichiometric oxidant or hydrogen atom transfer reagents required in previous studies, the scalable benchtop approach can execute α-C–H bond functionalization of THF only by a QD photocatalyst under redox-neutral condition, thus providing a broad of value added chemicals starting from bulk THFs reagent. The high step- and atom-economy, high efficiency and broad substrate scope make the photocatalysis with QDs and visible light promising in both academic and industrial setting.
Jamie A. Cadge, , Christopher A. Russell
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202108744

Abstract:
A combined theoretical and experimental approach has been used to study the unusual mechanism of oxidative addition of aryl iodides to [bipyAu(C 2 H 4 )] + complexes. The modular nature of this system has allowed a systematic assessment of the effects of complex structure. Computational comparisons between cationic gold and the isolobal (neutral) Pd(0) and Pt(0) complexes revealed similar mechanistic features, but with oxidative addition being significantly favored for the group 10 metals. Further differences between Au and Pd were seen in experimental studies: studying reaction rates as a function of electronic and steric properties showed that ligands bearing more electron-poor functionality increase the rate of oxidative addition; in a complementary way, electron-rich aryl iodides give faster rates. This divergence in mechanism compared to Pd suggests that Ar-X oxidative addition with Au can underpin a broad range of new or complementary transformations.
Raffaele Senatore, Monika Malik, Thierry Langer, Wolfgang Holzer,
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110641

Abstract:
A formal CH 2 -CH 2 homologation conducted with C1 carbenoids on a carbon electrophile for the obtainment of a four-membered cycle is reported. The logic proposes the consecutive delivery of two single nucleophilic CH 2 units to an isothiocyanate – as competent electrophilic partner – resulting in the assembling of a rare imino-thietane cluster. The single synthetic operation procedure documents genuine chemocontrol, as indicated by the tolerance to various reactive elements decorating the starting materials. Significantly, the double homologation protocol is accomplished directly on a carbon electrophile, thus not requiring the installation of heteroatom-centered manifolds ( e.g. boron).
Tal Gilboa, Limor Cohen, Chi-An Cheng, Roey Lazarovits, Augusta Uwamanzu-Nna, Isaac Han, Kettner Griswold, Nick Barry, David B. Thompson, Richie E. Kohman, et al.
Angewandte Chemie International Edition; https://doi.org/10.1002/anie.202110702

Abstract:
Coronavirus disease 2019 (COVID-19) manifests with high clinical variability and warrants sensitive and specific assays to analyze immune responses in infected and vaccinated individuals. Using Single Molecule Arrays (Simoa), we developed an assay to assess antibody neutralization with high sensitivity and multiplexing capabilities based on antibody-mediated blockage of the ACE2-spike interaction. The assay does not require live viruses or cells and can be performed in a biosafety level 2 laboratory within two hours. We used this assay to assess neutralization and antibody levels in patients who died of COVID-19 and patients hospitalized for a short period of time, and show that neutralization and antibody levels increase over time. We also adapted the assay for SARS-CoV-2 variants and measured neutralization capacity in pre-pandemic healthy, COVID-19 infected, and vaccinated individuals. This assay is highly adaptable for clinical applications, such as vaccine development and epidemiological studies.
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