Chemistry - A European Journal最新文献_第3页

EXPLORING SINGLE ATOM SUBSTITUTION IN PHENANTHRO[9,10-D]IMIDAZOLE -BASED D-π-A ARCHITECTURES WITH FLUORENE AND ITS HETEROANALOGS FOR NON-VOLATILE RESISTIVE WORM MEMORY DEVICE APPLICATIONS.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-29 DOI: 10.1002/chem.202404337

Madanan Akshaya, Ramesh Gayathri, Predhanekar Mohamed Imran, Samuthira Nagarajan

{"title":"EXPLORING SINGLE ATOM SUBSTITUTION IN PHENANTHRO[9,10-D]IMIDAZOLE -BASED D-π-A ARCHITECTURES WITH FLUORENE AND ITS HETEROANALOGS FOR NON-VOLATILE RESISTIVE WORM MEMORY DEVICE APPLICATIONS.","authors":"Madanan Akshaya, Ramesh Gayathri, Predhanekar Mohamed Imran, Samuthira Nagarajan","doi":"10.1002/chem.202404337","DOIUrl":"https://doi.org/10.1002/chem.202404337","url":null,"abstract":"A series of D-π-A compounds, with fluorene and its heteroanalogs (carbazole, dibenzofuran, dibenzothiophene) as the donor units and phenanthroimidazole as the acceptor, were designed and synthesized for non-volatile memory device applications. The effect of single-atom substitution on memory behavior was examined through optical, electrochemical, and computational studies. The photophysical studies confirm a significant intramolecular charge transfer from the donor to the acceptor unit, and the electrochemical analysis shows an irreversible anodic peak (0.99-1.21 V) with an optimal band gap ranging from 2.80 to 2.88 eV. All the compounds exhibited non-volatile binary WORM memory behaviour with an ON/OFF current ratio of 105 and 103. The devices also showed excellent stability over 100 cycles and maintained a retention time of 4000 s. Notably, the compound with carbazole substitution displayed a lower threshold voltage and a higher ON/OFF current ratio of 105. Density functional theory calculations confirmed that the combined effects of charge transfer and charge trapping mechanisms are crucial to the resistive switching mechanisms observed. This work highlights the potential of single atom substitution in D-π-A systems, providing valuable insights for designing high-performance data storage devices.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e202404337"},"PeriodicalIF":3.9,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143062635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring Divergent Role of Amine in Chemodivergent Synthesis of 4-alkyl/aryl-3H-1,2-Dithiole-3-thione and Ketothioamide.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-29 DOI: 10.1002/chem.202404346

Ankush Gupta, Guddeangadi N Gururaja

引用次数: 0

Exploring the Synthesis and Properties of Fluorinated Cationic Triangulenes and their Precursors.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-29 DOI: 10.1002/chem.202404135

Ramandeep Kaur, Jules Moutet, David Mills, Thomas L Gianetti

引用次数: 0

Electrocatalytic Reduction of CO2 to Long-Chain Hydrocarbons: Investigating the asymmetric C-C Coupling Mechanism on Pd3Au Catalysts.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-29 DOI: 10.1002/chem.202404354

Ming Zheng, Chade Lv, Xin Zhou

{"title":"Electrocatalytic Reduction of CO2 to Long-Chain Hydrocarbons: Investigating the asymmetric C-C Coupling Mechanism on Pd3Au Catalysts.","authors":"Ming Zheng, Chade Lv, Xin Zhou","doi":"10.1002/chem.202404354","DOIUrl":"https://doi.org/10.1002/chem.202404354","url":null,"abstract":"The electrochemical reduction of CO2 to high-energy-density hydrocarbons is pivotal for addressing energy and environmental challenges. Understanding the mechanisms underlying the conversion of CO2 to long-chain hydrocarbons is both crucial and complex. In this study, we employed density functional theory (DFT) calculations to investigate the C-C coupling mechanisms responsible for the formation of C2-C4 products on Pd3Au catalysts. Our findings highlight the sequential formation of C2-C1 bonds via asymmetric C-C coupling as a critical pathway for generating C3 product, which is essential for controlling product selectivity. Detailed analysis of coupling reactions involving CCH2* and CCH3* intermediates with various C1 species indicates that these asymmetric coupling events are energetically favorable and play a decisive role in the selective assembly of carbon atoms into longer hydrocarbon chains. Moreover, we propose a mechanism wherein the asymmetric coupling of C1-C3 intermediate leads to a diverse array of C4 products. This process underscores the importance of CH2 group coupling with C3 intermediates in forming long-chain hydrocarbons. Our work provides valuable insights into optimizing catalyst design for improved selectivity towards higher hydrocarbons in CO2 reduction processes.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e202404354"},"PeriodicalIF":3.9,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143062628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of pH-Responsive SA/PEGDA/AS-POSS Hydrogels via Michael Addition for Controlled Drug Release and Enhanced Mechanical Properties.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-29 DOI: 10.1002/chem.202404538

Yang Meng, Wen Li, Lingji Zhang, Mario Berrettoni, Hongzhong Zhang, Xiaojing Zhang

{"title":"Development of pH-Responsive SA/PEGDA/AS-POSS Hydrogels via Michael Addition for Controlled Drug Release and Enhanced Mechanical Properties.","authors":"Yang Meng, Wen Li, Lingji Zhang, Mario Berrettoni, Hongzhong Zhang, Xiaojing Zhang","doi":"10.1002/chem.202404538","DOIUrl":"https://doi.org/10.1002/chem.202404538","url":null,"abstract":"In this study, thiolated sodium alginate (SA) and hydrophilic, polymerizable Janus-type polyhedral oligomeric silsesquioxane (AS-POSS) are synthesized by introducing thiol and sulfonic acid groups, respectively. A series of pH-responsive SA/PEGDA/AS-POSS nanocomposite hydrogels are successfully prepared through Michael addition reactions between the thiol groups of thiolated sodium alginate and the double bonds in the molecular chains of AS-POSS and poly(ethylene glycol) diacrylate (PEGDA). This reaction proceeds rapidly under physiological conditions without requiring initiators or catalysts. As the content of AS-POSS increases, the pore size within the hydrogel decreases, and the network structure becomes denser, with significant improvements in mechanical properties. The hydrogel exhibits excellent pH sensitivity, showing lower swelling in acidic media compared to neutral media, and undergoing hydrolysis and losing stability in alkaline media. Moreover, the incorporation of AS-POSS significantly enhances the drug-loading capacity (85.7%) and encapsulation efficiency (72.1%) of doxorubicin (DOX). The drug is released faster in weakly acidic environments, with a cumulative release rate reaching 80.4%, demonstrating excellent targeting and controlled release properties. Cytotoxicity tests show that the SA/PEGDA/AS-POSS hydrogel has good biocompatibility and exhibits effective tumor-killing ability, indicating its great potential as a drug carrier with promising applications in biomedical materials.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e202404538"},"PeriodicalIF":3.9,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143062556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Incorporation of Cages into Gels: Access to a New Class of Soft Materials with Well-Defined Functionality.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-28 DOI: 10.1002/chem.202404363

Jie Zhao, Yijie Zhang, Zhe Wang, Dong Yang

引用次数: 0

Development of Triphenylamine Derived Photosensitizers for Efficient Hydrogen Evolution from Water.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-28 DOI: 10.1002/chem.202404542

Yudong Wen, Linyu Fan, Xiao Yao, Cheuk-Lam Ho

{"title":"Development of Triphenylamine Derived Photosensitizers for Efficient Hydrogen Evolution from Water.","authors":"Yudong Wen, Linyu Fan, Xiao Yao, Cheuk-Lam Ho","doi":"10.1002/chem.202404542","DOIUrl":"https://doi.org/10.1002/chem.202404542","url":null,"abstract":"A series of new (donor)₂-donor-π-acceptor (D2-D-π-A) and (acceptor)₂-donor-π-acceptor (A2-D-π-A) organic photosensitizers based on the framework of (Z)-2-cyano-3-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)acrylic acid have been synthesized and characterized. By incorporating groups with different electron-donating or withdrawing abilities, such as dibenzothiophene (DBT), dibenzofuran (DBF), and triazine (TA), into the triphenylamine segment, their photophysical properties have been regulated. Theoretical calculations were used to explore how various donor-acceptor combinations influence their hydrogen production performance. Notably, DBF-CN achieved the highest turnover number (TON) of 10,202 and an initial turnover frequency (TOFi) of 151.6 h⁻¹ under green light irradiation, with an initial activity (Activityi) of 113,532 μmol g⁻¹ h⁻¹ and an apparent quantum yield (AQYi) of 0.76%. This dye-sensitized-TiO2-Pt system is recognized as one of the most efficient and durable systems for photocatalytic hydrogen production under green light irradiation, as described in the literature, when compared using TOF and TON values. Experimental results indicate that the D2-D-π-A system significantly enhances photocatalytic hydrogen evolution (PHE) performance more effectively than the A2-D-π-A system, while also maintaining stability under prolonged light exposure.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e202404542"},"PeriodicalIF":3.9,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143051126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nickel-Catalyzed Selective Reduction of Carbon Monoxide with Magnesium Alkyl Compounds.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-28 DOI: 10.1002/chem.202404594

Mengwei Wang, Yanping Cai, Thayalan Rajeshkumar, Laurent Maron, Xin Xu

引用次数: 0

Improving the Long-term Enantioselectivity of a Silicon-Carbon Bond-Forming Enzyme.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-28 DOI: 10.1002/chem.202404688

Annika J Weber, Celine Moser, Maria Alessandra Martini, Franziska J Laß, Katharina Bleher, Claudia Muhle-Goll, Christof M Niemeyer, Kersten S Rabe

{"title":"Improving the Long-term Enantioselectivity of a Silicon-Carbon Bond-Forming Enzyme.","authors":"Annika J Weber, Celine Moser, Maria Alessandra Martini, Franziska J Laß, Katharina Bleher, Claudia Muhle-Goll, Christof M Niemeyer, Kersten S Rabe","doi":"10.1002/chem.202404688","DOIUrl":"https://doi.org/10.1002/chem.202404688","url":null,"abstract":"Enantioselectivity is a key advantage of enzymatic catalysis. Understanding the most important factors influencing enantioselectivity necessitates thorough investigation for each specific enzyme. In this study, we explore various approaches to optimize reaction conditions for organosilicon production using an immobilized Cytochrome C recently tailored via directed evolution. Over extended reactions, this enzyme experiences a loss of enantioselectivity. Mass spectrometry (MS) revealed covalent modifications on the enzyme, but mutating the respective amino acids did not restore enantioselectivity. Nuclear magnetic resonance (NMR), along with a detailed comparison of the influence of reaction components such as cosolvents and reducing agents, indicated significant conformational changes in the presence of the diazo ester substrate. Additionally, we identified sodium ascorbate as a suitable and milder reducing agent compared to the previously used sodium dithionite, ensuring anaerobic conditions for silicon-carbon bond formation. Ultimately, maintaining a high enzyme-to-substrate ratio in the reaction was found to be crucial for achieving high enantiomeric purity of the organosilicon product over four days in sequential, repetitive batch reactions, thus improving the previously established reaction system. The methods and findings presented here are particularly valuable for addressing enantioselectivity issues in other enzymes that operate with diazo compounds as the substrates in carbene-transfer reactions.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e202404688"},"PeriodicalIF":3.9,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143057596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Near-neutral pH sensing by azoheteroarene dyes.

IF 3.9 2区化学

Chemistry - A European Journal Pub Date : 2025-01-28 DOI: 10.1002/chem.202403897

Hashim P K, Shifa Ahmad, Nusaiba Madappuram Cheruthu, Saugata Sahu, Nobuyuki Tamaoki

引用次数: 0