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ChemDigest – Basic bits and bolts of chemistry

Discovery of a Potent and Orally Bioavailable Zwitterionic Series of Selective Estrogen Receptor Degrader-Antagonists

Par / 2 février 2023 / medchem

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Journal of Medicinal Chemistry

Journal of Medicinal Chemistry: Latest Articles (ACS Publications)
Authors: James S. Scott, Darren Stead, Bernard Barlaam, Jason Breed, Rodrigo J. Carbajo, Elisabetta Chiarparin, Natalie Cureton, Paul R. J. Davey, David I. Fisher, Eric T. Gangl, Tyler Grebe, Ryan D. Greenwood, Sudhir Hande, Holia Hatoum-Mokdad, Samantha J. Hughes, Thomas A. Hunt, Tony Johnson, Stefan L. Kavanagh, Teresa C. M. Klinowska, Carrie J. B. Larner, Mandy Lawson, Andrew S. Lister, David Longmire, Stacey Marden, Thomas M. McGuire, Caroline McMillan, Lindsay McMurray, Christopher J. Morrow, J. Willem M. Nissink, Thomas A. Moss, Daniel H. O’Donovan, Radoslaw Polanski, Stephen Stokes, Kumar Thakur, Dawn Trueman, Caroline Truman, Michael J. Tucker, Haixia Wang, Nicky Whalley, Dedong Wu, Ye Wu, Bin Yang, and Wenzhan Yang
dx.doi.org/http://dx.doi.org/10.1021/acs.jmedchem.2c01964

Discovery of a Novel Potent and Selective HSD17B13 Inhibitor, BI‑3231, a Well-Characterized Chemical Probe Available for Open Science

Par / 2 février 2023 / medchem

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Journal of Medicinal Chemistry

Journal of Medicinal Chemistry: Latest Articles (ACS Publications)
Authors: Sven Thamm, Marina K. Willwacher, Gary E. Aspnes, Tom Bretschneider, Nicholas F. Brown, Silke Buschbom-Helmke, Thomas Fox, Emanuele M. Gargano, Daniel Grabowski, Christoph Hoenke, Damian Matera, Katja Mueck, Stefan Peters, Sophia Reindl, Doris Riether, Matthias Schmid, Christofer S. Tautermann, Aaron M. Teitelbaum, Cornelius Trünkle, Thomas Veser, Martin Winter, and Lars Wortmann
dx.doi.org/http://dx.doi.org/10.1021/acs.jmedchem.2c01884

Strain-Driven Solid–Solid Crystal Conversion in Chiral Hybrid Pseudo-Perovskites with Paramagnetic-to-Ferromagnetic Transition

Par / 2 février 2023 / Non classé

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Journal of the American Chemical Society

Journal of the American Chemical Society: Latest Articles (ACS Publications)
Authors: Haining Zheng, Rongrong Zhang, Xiao Wu, Qihan Zhang, Zhenyue Wu, Walter P. D. Wong, Jingsheng Chen, Qing-Hua Xu, and Kian Ping Loh
dx.doi.org/https://doi.org/10.1021/jacs.2c12525

ortho-Methoxycarbonylethynylphenyl Thioglycosides (MCEPTs): Versatile Glycosyl Donors Enabled by Electron-Withdrawing Substituents and Catalyzed by Gold(I) or Cu(II) Complexes

Par / 2 février 2023 / Non classé

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Journal of the American Chemical Society

Journal of the American Chemical Society: Latest Articles (ACS Publications)
Authors: Hui Liu, Zhi-Fen Liang, Han-Jian Liu, Jin-Xi Liao, Li-Jun Zhong, Yuan-Hong Tu, Qing-Ju Zhang, Bin Xiong, and Jian-Song Sun
dx.doi.org/https://doi.org/10.1021/jacs.2c13018

First Total Synthesis of the Benzotropolone/Bis(pulvinone) Natural Product Aurantricholone Exploiting New Strategies for Establishing Benzotropolones and Z‐Configured Pulvinones

Par / 2 février 2023 / Non classé
First Total Synthesis of the Benzotropolone/Bis(pulvinone) Natural Product Aurantricholone Exploiting New Strategies for Establishing Benzotropolones and Z-Configured Pulvinones

The fungal colorant aurantricholone was synthesized in 15 steps. Its benzotropolone core resulted from 5-bromo-7,8-dimethoxytetral-1-one in 3 steps which included a 1-pot ring-enlargement/oxidation/acetylation sequence. A regioselective 2-step bromination allowed two Z-selective Suzuki couplings with a new tetronate building block to ensue in one go. Deprotection (2 steps) gave protonated aurantricholone or its Li or Ca salt.

Abstract

Aurantricholone as well as its calcium and lithium salts, all of which represent the coloring principle of the fungus Tricholoma aurantium, were synthesized for the first time, namely in 15 steps, 10 of which were our longest linear sequence. We developed an access to benzotropolones after dibromocyclopropanating alkyl or silyl enol ethers of 1-tetralones. Successive treatments with DMAP-N-oxide and Ac2O effected ring-enlargement, oxidation, and acetylation. O-acetyl-1-bromo-3,4-dimethoxybenzotropolone obtained thereby – similarly as unsubstituted benzotropolone – was brominated at C-8 in two steps by adopting our recently published bromination protocol for otherwise unsubstituted O-acetylbenzotropolone. Thereafter, a double and doubly Z-selective Suzuki-coupling with a newly introduced boronate established the O-methylated pulvinone moiety as well as the O-methylated “pulvinone-like” motif of what altogether equaled the completed aurantricholone scaffold. Its deprotection (two steps) furnished the title compound either as its protonated form or its calcium or lithium salt.

Wiley: European Journal of Organic Chemistry: Table of Contents
Authors: Philip Koblischek, Reinhard Brückner
chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/ejoc.202201120

Modulating Thermal Properties of Polymers through Crystal Engineering

Par / 1 février 2023 / Non classé
Modulating Thermal Properties of Polymers through Crystal Engineering

Crystal engineering of multicomponent solids involving both small and polymeric molecules resulted in the preparation of cocrystals with melting points higher than the melting point of the pure polymer. At the same time, the high mechanical flexibility of the polymer is maintained even under harsh milling conditions, allowing the formation of toroidal nanoparticles with small inner radii and high curvatures.

Abstract

Crystal engineering has exclusively focused on the development of advanced materials based on small organic molecules. We now demonstrate how the cocrystallization of a polymer yields a material with significantly enhanced thermal stability but equivalent mechanical flexibility. Isomorphous replacement of one of the cocrystal components enables the formation of solid solutions with melting points that can be readily fine-tuned over a usefully wide temperature range. The results of this study credibly extend the scope of crystal engineering and cocrystallization from small molecules to polymers.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Luzia S. Germann, Elvio Carlino, Antonietta Taurino, Oxana V. Magdysyuk, Dario Voinovich, Robert E. Dinnebier, Dejan‐Krešimir Bučar, Dritan Hasa
onlinelibrary.wiley.com/doi/10.1002/anie.202212688

Revealing the Formation Mechanism and Optimizing the Synthesis Conditions of Layered Double Hydroxides for the Oxygen Evolution Reaction

Par / 1 février 2023 / Non classé
Revealing the Formation Mechanism and Optimizing the Synthesis Conditions of Layered Double Hydroxides for the Oxygen Evolution Reaction

The combination of NH3 gas diffusion and in situ pH measurement provides a way to investigate the effect of the real-time change of OH− concentration on layered double hydroxide (LDH) formation. The results revealed the formation mechanism of LDHs and also guided the synthesis of a library of LDHs with desired attributes, in water at room temperature without using any additives.

Abstract

Layered double hydroxides (LDHs), whose formation is strongly related to OH− concentration, have attracted significant interest in various fields. However, the effect of the real-time change of OH− concentration on LDHs’ formation has not been fully explored due to the unsuitability of the existing synthesis methods for in situ characterization. Here, the deliberately designed combination of NH3 gas diffusion and in situ pH measurement provides a solution to the above problem. The obtained results revealed the formation mechanism and also guided us to synthesize a library of LDHs with the desired attributes in water at room temperature without using any additives. After evaluating their oxygen evolution reaction performance, we found that FeNi-LDH with a Fe/Ni ratio of 25/75 exhibits one of the best performances so far reported.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zongkun Chen, Xingkun Wang, Zhongkang Han, Siyuan Zhang, Simone Pollastri, Qiqi Fan, Zhengyao Qu, Debalaya Sarker, Christina Scheu, Minghua Huang, Helmut Cölfen
onlinelibrary.wiley.com/doi/10.1002/anie.202215728

Metal Organic Framework Cubosomes

Par / 1 février 2023 / Non classé
Metal Organic Framework Cubosomes

This study developed a general strategy for the synthesis of ordered metal organic framework (MOF) cubosomes with a single primitive bicontinuous structure by using polymer cubosomes as the template, and also studied their growth mechanism and kinetics as well as potential proteolysis application.

Abstract

We demonstrate a general strategy for the synthesis of ordered bicontinuous-structured metal organic frameworks (MOFs) by using polymer cubosomes (PCs) with a double primitive structure (Imm symmetry) as the template. The filling of MOF precursors in the open channel of PCs, followed by their coordination and removal of the template, generates MOF cubosomes with a single primitive topology (Pmm) and average mesopore diameters of 60–65 nm. Mechanism study reveals that the formation of ZIF-8 cubosomes undergoes a new MOF growth process, which involves the formation of individual MOF seeds in the template, their growth and eventual fusion into the cubosomes. Their growth kinetics follows the Avrami equation with an Avrami exponent of n=3 and a growth rate of k=1.33×10−4, indicating their fast 3D heterogeneous growth mode. Serving as a bioreactor, the ZIF-8 cubosomes show high loading of trypsin enzyme, leading to a high catalytic activity in the proteolysis of bovine serum albumin.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Chen Li, Yi Pan, Tianyu Xiao, Luoxing Xiang, Qian Li, Feng Tian, Ian Manners, Yiyong Mai
onlinelibrary.wiley.com/doi/10.1002/anie.202215985

Direct Monitoring of Li2S2 Evolution and Its Influence on the Reversible Capacities of Lithium‐Sulfur Batteries

Par / 1 février 2023 / Non classé
Direct Monitoring of Li2S2 Evolution and Its Influence on the Reversible Capacities of Lithium-Sulfur Batteries

A series of operando spectral results reveal that Li2S2 undergoes chemical reactions accompanied by its electrochemical conversions during operation for the first time. The chemical reactions related to Li2S2 can increase polysulfide dissolution and Li2S generation without capacity contribution. Instead of the commonly considered Li2S, Li2S2 is the solid “dead” sulfur species and restricts the actual sulfur utilization and reversible capacity.

Abstract

The polysulfide (PS) dissolution and low conductivity of lithium sulfides (Li2S) are generally considered the main reasons for limiting the reversible capacity of the lithium-sulfur (Li-S) system. However, as the inevitable intermediate between PSs and Li2S, lithium disulfide (Li2S2) evolutions are always overlooked. Herein, Li2S2 evolutions are monitored from the operando measurements on the pouch cell level. Results indicate that Li2S2 undergoes slow electrochemical reduction and chemical disproportionation simultaneously during the discharging process, leading to further PS dissolution and Li2S generation without capacity contribution. Compared with the fully oxidized Li2S, Li2S2 still residues at the end of the charging state. Therefore, instead of the considered Li2S and PSs, slow electrochemical conversions and side chemical reactions of Li2S2 are the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li-S batteries.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yufeng Luo, Zhenhan Fang, Shaorong Duan, Hengcai Wu, Haitao Liu, Yuxing Zhao, Ke Wang, Qunqing Li, Shoushan Fan, Zijian Zheng, Wenhui Duan, Yuegang Zhang, Jiaping Wang
onlinelibrary.wiley.com/doi/10.1002/anie.202215802

Low Concentration Sulfolane‐Based Electrolyte for High Voltage Lithium Metal Batteries

Par / 1 février 2023 / Non classé
Low Concentration Sulfolane-Based Electrolyte for High Voltage Lithium Metal Batteries

We developed a low concentration electrolyte (LCE) (0.25 M) with low solubility LiNO3 as the main salt. This LCE shows good separator wettability, high ionic conductivity, high Li+ transference number, and low cost. The rational design of the interphases enables LCE to be suitable for high-voltage lithium metal batteries.

Abstract

Electrolyte engineering is crucial for the commercialization of lithium metal batteries. Here, lithium metal is stabilized in the highly reactive sulfolane-based electrolyte under low concentration (0.25 M) for the first time. Inorganic-polymer hybrid solid electrolyte interphase (SEI) with high ionic conductivity, low bonding with lithium and high flexibility enables dense chunky lithium deposition and high plating/stripping efficiency. Low concentration electrolyte (LCE) also enables excellent cycling stability of LiNi0.5Co0.2Mn0.3O2 (NCM523)/Li cells at 1 C (90.7 % retention after 500 cycles) and 0.3 C (83.3 % retention after 1000 cycles). With a low N/P ratio (≈2), the capacity retention for NCM523/Li cells can achieve 94.3 % after 100 cycles at 0.3 C. Exploring the LCE is of paramount significance because it provides more possibilities of the lithium salt selections, especially reviving some lithium salts that are excluded before due to their low solubility. More importantly, LCE has the significant advantage of commercialization due to its cost-effectiveness.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Pengcheng Li, Hao Zhang, Jun Lu, Ge Li
onlinelibrary.wiley.com/doi/10.1002/anie.202216312

Turning on the Antimicrobial Activity of Gold Nanoclusters Against Multidrug‐Resistant Bacteria

Par / 1 février 2023 / Non classé
Turning on the Antimicrobial Activity of Gold Nanoclusters Against Multidrug-Resistant Bacteria**

“Turning-on” the antimicrobial activity of gold nanoclusters. The addition of thiourea enabled the broad-spectrum antimicrobial activity of otherwise inactive gold nanoclusters against multidrug-resistant bacteria.

Abstract

In this work, we show that the addition of thiourea (TU) initiated broad-spectrum antimicrobial activity of otherwise inactive D-maltose-capped gold nanoclusters (AuNC-Mal). For example, AuNC-Mal/TU was effective against multidrug-resistant Pseudomonas aeruginosa with a minimum inhibitory concentration (MIC) of 1 μg mL−1 (2.5 μM [Au]) while having 30–60 times lower in vitro cytotoxicity against mammalian cells. The reaction of AuNC-Mal and TU generated the antimicrobial species of [Au(TU)2]+ and smaller AuNCs. TU increased the accumulation of Au in bacteria and helped maintain the oxidation state as AuI (vs. AuIII). The modes of action included the inhibition of thioredoxin reductase, interference with the CuI regulation and depletion of ATP. Moreover, the antimicrobial activity did not change in the presence of colistin or carbonyl cyanide 3-chlorophenylhydrazone, suggesting that AuNC-Mal/TU was indifferent to the outer membrane barrier and to bacterial efflux pumps.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: William Ndugire, Dang Truong, N. G. Hasitha Raviranga, Jingzhe Lao, Olof Ramström, Mingdi Yan
onlinelibrary.wiley.com/doi/10.1002/anie.202214086

Enantioselective N‐Heterocyclic Carbene Catalyzed α‐Oxidative Coupling of Enals with Carboxylic Acids Using an Iodine(III) Reagent

Par / 1 février 2023 / Non classé
Enantioselective N-Heterocyclic Carbene Catalyzed α-Oxidative Coupling of Enals with Carboxylic Acids Using an Iodine(III) Reagent

Umpolung of an NHC-bound enolate with an iodine(III) reagent was developed to enable enantioselective α-oxidative coupling of enals with carboxylic acids, affording α-acyloxyl-β,γ-unsaturated esters in good yields with high regio- and enantioselectivities. The key step involves the formation of an enol iodine(III) intermediate, which changes the polarity of α-carbon of the enal from nucleophilic to electrophilic.

Abstract

The enantioselective α-oxidative coupling of enals with carboxylic acids was developed via the umpolung of an NHC-bound enolate with an iodine(III) reagent. The corresponding α-acyloxyl-β,γ-unsaturated esters were afforded in good yields, with high regio- and enantioselectivities. The key step of the reaction involves the formation of enol iodine(III) intermediate from the enolate with iodosobenzene, which changes the polarity of α-carbon of the enal from nucleophilic to electrophilic, and thus facilitates the subsequent addition of carboxylate.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yuan‐Yuan Xu, Zhong‐Hua Gao, Cao‐Bo Li, Song Ye
onlinelibrary.wiley.com/doi/10.1002/anie.202218362

Second Sphere Effects Promote Formic Acid Dehydrogenation by a Single‐Atom Gold Catalyst Supported on Amino‐Substituted Graphdiyne

Par / 1 février 2023 / Non classé
Second Sphere Effects Promote Formic Acid Dehydrogenation by a Single-Atom Gold Catalyst Supported on Amino-Substituted Graphdiyne

A gold (Au) single-atom catalyst (SAC) supported on amino-functionalized graphdiyne was synthesized, which displayed a fivefold higher catalytic activity than the Au SAC supported on graphdiyne. Experimental and computational studies reveal that the amino groups in the second sphere of the Au atom serve as proton relays to facilitate the H2 formation from an Au−H intermediate, thus substantially accelerating the rate of formic acid dehydrogenation.

Abstract

Regulating the second sphere of homogeneous molecular catalysts is a common and effective method to boost their catalytic activities, while the second sphere effects have rarely been investigated for heterogeneous single-atom catalysts primarily due to the synthetic challenge for installing functional groups in their second spheres. Benefiting from the well-defined and readily tailorable structure of graphdiyne (GDY), an Au single-atom catalyst on amino-substituted GDY is constructed, where the amino group is located in the second sphere of the Au center. The Au atoms on amino-decorated GDY displayed superior activity for formic acid dehydrogenation compared with those on unfunctionalized GDY. The experimental studies, particularly the proton inventory studies, and theoretical calculations revealed that the amino groups adjacent to an Au atom could serve as proton relays and thus facilitate the protonation of an intermediate Au−H to generate H2. Our study paves the way to precisely constructing the functional second sphere on single-atom catalysts.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Hong Liu, Haiyuan Zou, Dan Wang, Chuancheng Wang, Fan Li, Hao Dai, Tao Song, Mei Wang, Yongfei Ji, Lele Duan
onlinelibrary.wiley.com/doi/10.1002/anie.202216739

Highly Effective Hybrid Copper(I) Iodide Cluster Emitter with Negative Thermal Quenched Phosphorescence for X‐Ray Imaging

Par / 1 février 2023 / Non classé
Highly Effective Hybrid Copper(I) Iodide Cluster Emitter with Negative Thermal Quenched Phosphorescence for X-Ray Imaging

The new hybrid copper(I) iodide cluster (DBA)4Cu4I4 enables ultra-bright triplet yellow-orange emission with a PLQY>94.9 % by the coaction of excited state structure reorganization and the metallophilicity interaction, and the phonon-assisted de-trapping process of exciton induces the negative thermal quenching effect at 80–300 K. Our investigation show that this material has a great potential in practical X-ray imaging applications.

Abstract

The low efficiency triplet emission of hybrid copper(I) iodide clusters is a critical obstacle to their further practical optoelectronic application. Herein, we present an efficient hybrid copper(I) iodide cluster emitter (DBA)4Cu4I4, where the cooperation of excited state structure reorganization and the metallophilicity interaction enables ultra-bright triplet yellow-orange emission with a photoluminescence quantum yield over 94.9 %, and the phonon-assisted de-trapping process of exciton induces the negative thermal quenching effect at 80–300 K. We also investigate the potential of this emitter for X-ray imaging. The (DBA)4Cu4I4 wafer demonstrates a light yield higher than 104 photons MeV−1 and a high spatial resolution of ≈5.0 lp mm−1, showing great potential in practical X-ray imaging applications. Our new copper(I) iodide cluster emitter can serve as a model for investigating the thermodynamic mechanism of photoluminescence in hybrid copper(I) halide phosphorescence materials.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Qingsong Hu, Chengkai Zhang, Xian Wu, Guijie Liang, Lei Wang, Xiaowei Niu, Zhi Wang, Wei‐Dan Si, Yibo Han, Ruiqin Huang, Jiawen Xiao, Di Sun
onlinelibrary.wiley.com/doi/10.1002/anie.202217784

Chemical Synthesis of Bioactive Proteins

Par / 1 février 2023 / Non classé
Chemical Synthesis of Bioactive Proteins

Protein chemistry has evolved remarkably in the past decade, which has enabled the effective production of new molecules with novel physicochemical properties for biomedical research, and therapeutic applications. This minireview summarizes recent developments in chemical protein synthesis to produce bioactive proteins, with emphasis on novel analogs with promising in vitro and in vivo activity.

Abstract

Nature has developed a plethora of protein machinery to operate and maintain nearly every task of cellular life. These processes are tightly regulated via post-expression modifications—transformations that modulate intracellular protein synthesis, folding, and activation. Methods to prepare homogeneously and precisely modified proteins are essential to probe their function and design new bioactive modalities. Synthetic chemistry has contributed remarkably to protein science by allowing the preparation of novel biomacromolecules that are often challenging or impractical to prepare via common biological means. The ability to chemically build and precisely modify proteins has enabled the production of new molecules with novel physicochemical properties and programmed activity for biomedical research, diagnostic, and therapeutic applications. This minireview summarizes recent developments in chemical protein synthesis to produce bioactive proteins, with emphasis on novel analogs with promising in vitro and in vivo activity.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Omer Harel, Muhammad Jbara
onlinelibrary.wiley.com/doi/10.1002/anie.202217716

In‐Situ Constructing A Heterogeneous Layer on Lithium Metal Anodes for Dendrite‐Free Lithium Deposition and High Li‐ion Flux

Par / 1 février 2023 / Non classé
In-Situ Constructing A Heterogeneous Layer on Lithium Metal Anodes for Dendrite-Free Lithium Deposition and High Li-ion Flux

A dense and heterogeneous artificial SEI film is constructed via in situ reaction of layered zinc silicate nanosheets with Li. The consecutive Li+-conductors promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of Li+, and lower the nucleation barrier.

Abstract

Constructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/LixZny are uniformly but nonconsecutively dispersed in the consecutive Li+-conductors of LixSiOy, Li2O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+-conductors can promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm−2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm−2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Hong‐Jun Liu, Cheng‐Ye Yang, Mei‐Chen Han, Chun‐Yu Yu, Xiaofeng Li, Zhong‐Zhen Yu, Jin Qu
onlinelibrary.wiley.com/doi/10.1002/anie.202217458

Boosting Hydrogen Production via Selective Two‐electron Mild Electrochemical Oxidation of Tetrahydroisoquinolines Completely to Dihydroisoquinolines

Par / 1 février 2023 / Non classé
Boosting Hydrogen Production via Selective Two-electron Mild Electrochemical Oxidation of Tetrahydroisoquinolines Completely to Dihydroisoquinolines

Selective two-electron mild electrochemical oxidation of tetrahydroisoquinolines to high-valued-added dihydroisoquinolines can promote hydrogen production with maximum efficiency, compared with the high energy consumption of four-electron deep oxidation to isoquinolines.

Abstract

Different from the previous study that biomass derivatives replace water oxidation for enhancing hydrogen production, we found that mild oxidation was more conductive to cathodic hydrogen production. In this study, maximum Faradaic efficiency (>99 %) and lower energy consumption for hydrogen production was achieved by precisely controlling the two-electron mild electrochemical oxidation of tetrahydroisoquinolines (THIQs) to dihydroisoquinolines (DHIQs) in place of the four-electron deep oxidation to isoquinolines (IQs). Moreover, the high value-added DHIQs were prepared from THIQs with high selectivity (>99 %) at the low potential of 1.36 V. Operando electrochemical Raman and density functional theory proved that the high selectivity was attributed to the regulable active species of NiOOH induced by the interaction of Co and Fe for preferentially breaking C−H bond rather than N−H of THIQs. This novel method provides important insight into efficient biomass-assisted hydrogen production.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zhaoyu Zhou, Xun Pan, Lingzhi Sun, Yanan Xie, Jingui Zheng, Lina Li, Guohua Zhao
onlinelibrary.wiley.com/doi/10.1002/anie.202216347

Enhanced Interfacial Electron Transfer by Asymmetric Cu‐Ov‐In Sites on In2O3 for Efficient Peroxymonosulfate Activation

Par / 1 février 2023 / Non classé
Enhanced Interfacial Electron Transfer by Asymmetric Cu-Ov-In Sites on In2O3 for Efficient Peroxymonosulfate Activation

Asymmetric Cu-Ov-In sites constructed on Cu-In2O3/Ov catalysts facilitate the PMS adsorption and faster electron transfer through the side-on adsorption of the O−O bond, thereby realizing efficient PMS activation to generate more SO4⋅− and ⋅OH rapidly, and enabling excellent degradation activity of refractory organic pollutants.

Abstract

Enhancing the peroxymonosulfate (PMS) activation efficiency to generate more radicals is vital to promote the Fenton-like reaction activity, however, how to promote the PMS adsorption and accelerate the interfacial electron transfer to boost its activation kinetics remains a great challenge. Herein, we prepared Cu-doped defect-rich In2O3 (Cu-In2O3/Ov) catalysts containing asymmetric Cu−Ov−In sites for PMS activation in water purification. The intrinsic catalytic activity is that the side-on adsorption configuration of the O−O bond (Cu−O−O−In) at the Cu-Ov-In sites significantly stretches the O−O bond length. Meanwhile, the Cu-Ov-In sites increase the electron density near the Fermi energy level, promoting more and faster electron transfer to the O−O bond for generating more SO4⋅− and ⋅OH. The degradation rate constant of tetracycline achieved by Cu-In2O3/Ov is 31.8 times faster than In2O3/Ov, and it shows the possibility of membrane reactor for practical wastewater treatment.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zhiyong Zhao, Pengfei Wang, Chunlin Song, Tao Zhang, Sihui Zhan, Yi Li
onlinelibrary.wiley.com/doi/10.1002/anie.202216403

Electrocrystallization Regulation Enabled Stacked Hexagonal Platelet Growth toward Highly Reversible Zinc Anodes

Par / 1 février 2023 / Non classé
Electrocrystallization Regulation Enabled Stacked Hexagonal Platelet Growth toward Highly Reversible Zinc Anodes

A control mechanism of electrolyte on zinc electrocrystallization is proposed and validated through cyclic and linear sulfone cosolvents. The inner Helmholtz plane (IHP) formed by vertical dipole array is able to convert the deposition into activation control by weakening the solvated ion adsorption at the interface, steering conformal stratiform Zn growth and preferred orientation of Zn electrocrystallization.

Abstract

Realizing durative flattened and dendrite-free zinc (Zn) metal configuration is the key to resolving premature battery failure caused by the internal short circuit, which is highly determined by the crystal growth in the electrocrystallization process. Herein, we report that regulating the molecular structure of the inner Helmholtz plane (HIP) can effectively convert the deposition into activation control by weakening the solvated ion adsorption at the interface. The moderated electrochemical reaction kinetics lower than the adatom self-diffusion rate steers conformal stratiform Zn growth and dominant Zn (0001) texture, achieving crystallographic optimization. Through in situ mediation of electrolyte engineering, orientational plating and stripping behaviors at edge-sites and tailored solvation structure immensely improve the utilization efficiency and total charge passed of Zn metal, even under extreme conditions, including high areal capacity (3 mAh cm−2) and wide temperature range (−40–60 °C).

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zeyu Shen, Jiale Mao, Guoping Yu, Weidong Zhang, Shulan Mao, Wei Zhong, Hao Cheng, Junze Guo, Jiahui Zhang, Yingying Lu
onlinelibrary.wiley.com/doi/10.1002/anie.202218452

Enantio‐ and Regioselective Electrooxidative Cobalt‐Catalyzed C−H/N−H Annulation with Alkenes

Par / 1 février 2023 / Non classé
Enantio- and Regioselective Electrooxidative Cobalt-Catalyzed C−H/N−H Annulation with Alkenes

Reported is the first electrooxidative cobalt-catalyzed enantioselective C−H/N−H annulation with olefins (up to 99 % ee) using tBu-Salox as chiral ligand. The cooperative effect between tBu-Salox and 3,4,5-trichloropyridine enabled the highly enantio- and regioselective C−H annulation with the more challenging α-olefins (up to 96 % ee and 97 : 3 rr). Mechanistic studies provided insights into the mechanism of this reaction.

Abstract

In recent years, the merging of electrosynthesis with 3d metal catalyzed C−H activation has emerged as a sustainable and powerful technique in organic synthesis. Despite the impressive advantages, the development of an enantioselective version remains elusive and poses a daunting challenge. Herein, we report the first electrooxidative cobalt-catalyzed enantio- and regioselective C−H/N−H annulation with olefins using an undivided cell at room temperature (up to 99 % ee). tBu-Salox, a rationally designed Salox ligand bearing a bulky tert-butyl group at the ortho-position of phenol, was found to be crucial for this asymmetric annulation reaction. A strong cooperative effect between tBu-Salox and 3,4,5-trichloropyridine enabled the highly enantio- and regioselective C−H annulation with the more challenging α-olefins without secondary bond interactions (up to 96 % ee and 97 : 3 rr). Cyclovoltametric studies, and the preparation, characterization, and transformation of cobaltacycle intermediates shed light on the mechanism of this reaction.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Qi‐Jun Yao, Fan‐Rui Huang, Jia‐Hao Chen, Ming‐Yu Zhong, Bing‐feng Shi
onlinelibrary.wiley.com/doi/10.1002/anie.202218533

Direct Probe of Electrochemical Pseudocapacitive pH Jump at a Graphene Electrode

Par / 1 février 2023 / Non classé
Direct Probe of Electrochemical Pseudocapacitive pH Jump at a Graphene Electrode**

Using surface-specific heterodyne-detected sum-frequency generation, we probe the structure and orientation of interfacial water at a graphene electrode and find phase transition-like changes. We attribute it to local pH change-induced pseudocapacitive charging/discharging of the CaF2 substrate of the graphene electrode. Our work evidences the molecular-level effects of pseudocapacitive charging at an electrode/aqueous electrolyte interface.

Abstract

Molecular-level insight into interfacial water at a buried electrode interface is essential in electrochemistry, but spectroscopic probing of the interface remains challenging. Here, using surface-specific heterodyne-detected sum-frequency generation (HD-SFG) spectroscopy, we directly access the interfacial water in contact with the graphene electrode supported on calcium fluoride (CaF2). We find phase transition-like variations of the HD-SFG spectra vs. applied potentials, which arises not from the charging/discharging of graphene but from the charging/discharging of the CaF2 substrate through the pseudocapacitive process. The potential-dependent spectra are nearly identical to the pH-dependent spectra, evidencing that the pseudocapacitive behavior is associated with a substantial local pH change induced by water dissociation between the CaF2 and graphene. Our work evidences the local molecular-level effects of pseudocapacitive charging at an electrode/aqueous electrolyte interface.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yongkang Wang, Takakazu Seki, Xuan Liu, Xiaoqing Yu, Chun‐Chieh Yu, Katrin F. Domke, Johannes Hunger, Marc T. M. Koper, Yunfei Chen, Yuki Nagata, Mischa Bonn
onlinelibrary.wiley.com/doi/10.1002/anie.202216604

Metal‐Free Far‐Red Light‐Driven Photolysis via Triplet Fusion to Enhance Checkpoint Blockade Immunotherapy

Par / 1 février 2023 / Non classé
Metal-Free Far-Red Light-Driven Photolysis via Triplet Fusion to Enhance Checkpoint Blockade Immunotherapy

A metal-free triplet fusion photolysis (TFP) system, consisting of a BODIPY photosensitizer and a perylene prodrug (PyCl), released an anti-cancer drug upon far-red light irradiation. Encapsulation of this TFP system and a 2,3-dioxygenase (IDO) inhibitor within a nanoparticle enabled far-red light-promoted checkpoint blockade immunotherapy for effective inhibition of both local and metastatic tumors under extremely low excitation (20 mW cm−2).

Abstract

Metal-free long-wavelength light-driven prodrug photoactivation is highly desirable for applications such as neuromodulation, drug delivery, and cancer therapy. Herein, via triplet fusion, we report on the far-red light-driven photo-release of an anti-cancer drug by coupling the boron-dipyrromethene (BODIPY)-based photosensitizer with a photocleavable perylene-based anti-cancer drug. Notably, this metal-free triplet fusion photolysis (TFP) strategy can be further advanced by incorporating an additional functional dopant, i.e. an immunotherapy medicine inhibiting the indoleamine 2,3-dioxygenase (IDO), with the far-red responsive triplet fusion pair in an air-stable nanoparticle. With this IDO inhibitor-assisted TFP system we observed efficient inhibition of primary and distant tumors in a mouse model at record-low excitation power, compared to other photo-assisted immunotherapy approaches. This metal-free TFP strategy will spur advancement in photonics and biophotonics fields.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Le Zeng, Lin‐Han Jiang, Jia‐Yao Li, Ling Huang, Yongzhi Chen, Nuo Yu, Lei Wang, Kai Huang, Jing Peng, Gang Han
onlinelibrary.wiley.com/doi/10.1002/anie.202218341

Substantial Improvement of an Epimerase for the Synthesis of D‐Allulose by Biosensor‐Based High‐Throughput Microdroplet Screening

Par / 1 février 2023 / Non classé
Substantial Improvement of an Epimerase for the Synthesis of D-Allulose by Biosensor-Based High-Throughput Microdroplet Screening

A modified D-allulose biosensor was combined with a microdroplet screening system to establish an ultrahigh-throughput screening strategy. Structure-guided rational design and directed evolution were conducted to remodel the SfDAE active pocket and its lid region for enhanced catalytic performance for the synthesis of D-allulose. This approach shows great potential for the design and optimization of biosensor-based microdroplet screening platforms.

Abstract

Biosynthesis of D-allulose has been achieved using ketose 3-epimerases (KEases), but its application is limited by poor catalytic performance. In this study, we redesigned a genetically encoded biosensor based on a D-allulose-responsive transcriptional regulator for real-time monitoring of D-allulose. An ultrahigh-throughput droplet-based microfluidic screening platform was further constructed by coupling with this D-allulose-detecting biosensor for the directed evolution of the KEases. Structural analysis of Sinorhizobium fredii D-allulose 3-epimerase (SfDAE) revealed that a highly flexible helix/loop region exposes or occludes the catalytic center as an essential lid conformation regulating substrate recognition. We reprogrammed SfDAE using structure-guided rational design and directed evolution, in which a mutant M3-2 was identified with 17-fold enhanced catalytic efficiency. Our research offers a paradigm for the design and optimization of a biosensor-based microdroplet screening platform.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Chao Li, Xin Gao, Hongbin Qi, Wei Zhang, Lei Li, Cancan Wei, Meijing Wei, Xiaoxuan Sun, Shusen Wang, Liyan Wang, Yingbin Ji, Shuhong Mao, Zhangliang Zhu, Masaru Tanokura, Fuping Lu, Hui‐Min Qin
onlinelibrary.wiley.com/doi/10.1002/anie.202216721