48 research outputs found

    CO2_2 Conversion to Esters by Fluoride-mediated Carboxylation of Organosilanes and Halide Derivatives

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    International audienceThe one-step conversion of CO2_2 to hetero-aromatic esters is presented under metal-free conditions. Using fluoride anions as promoters for C-Si bond activation, pyridyl, furanyl and thiophenyl organosilanes are successfully carboxylated with CO2_2, in the presence of an electrophile. The mechanism of this unprecedented reaction has been elucidated based on experimental and computational results, which show a unique catalytic influence of CO2_2 in the C-Si bond activation of pyridylsilanes. The methodology is applied to 18 different esters and it has enabled the incorporation of CO2_2 to a polyester material, for the first time

    Hydrogenative depolymerization of nylons

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    This research was supported by the European Research Council (ERC AdG 692775). D. M. holds the Israel Matz Professorial Chair of Organic Chemistry. A. K. is thankful to the Planning and Budgeting Committee of Israel and Feinberg Graduate School for a (senior) postdoctoral fellowship. Y.-Q. Z. acknowledges the Sustainability and Energy ResearchInitiative (SAERI) foundation for a research fellowship. Computations were performed using HPC resources from GENCI-CINES (Grant 2019 AP010811227).The widespread crisis of plastic pollution demands discovery of new and sustainable approaches to degrade robust plastics such as nylons. Using a green and sustainable approach based on hydrogenation, in the presence of a ruthenium pincer catalyst at 150 oC and 70 bar H2, we report here the first example of hydrogenative depolymerization of conventional, widely used nylons, and polyamides in general. Un-der the same catalytic conditions, we also demonstrate the hydrogenation of a polyurethane to produce diol, diamine and methanol. Additionally, we demonstrate an example where monomers (and oligomers) obtained from the hydrogenation process can be dehydrogenated back to a poly(oligo)amide of approximately similar molecular weight, thus completing a closed loop cycle for recycling of poly-amides. Based on the experimental and DFT studies, we propose a catalytic cycle for the process that is facilitated by metal-ligand cooperativity. Overall, this unprecedented transformation, albeit at the proof of concept level, offers a new approach towards a cleaner route to recycling nylons.Publisher PDFPeer reviewe

    Management of patients undergoing CAR-T cell therapy in Germany

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    Introduction: Chimeric antigen receptor positive T cell (CAR-T cell) treatment became standard therapy for relapsed or refractory hematologic malignancies, such as non-Hodgkin’s lymphoma and multiple myeloma. Owing to the rapidly progressing field of CAR-T cell therapy and the lack of generally accepted treatment guidelines, we hypothesized significant differences between centers in the prevention, diagnosis, and management of short- and long-term complications. Methods: To capture the current CAR-T cell management among German centers to determine the medical need and specific areas for future clinical research, the DAG-HSZT (Deutsche Arbeitsgemeinschaft fĂŒr HĂ€matopoetische Stammzelltransplantation und ZellulĂ€re Therapie; German Working Group for Hematopoietic Stem Cell Transplantation and Cellular Therapy) performed a survey among 26 German CAR-T cell centers. Results: We received answers from 17 centers (65%). The survey documents the relevance of evidence in the CAR-T cell field with a homogeneity of practice in areas with existing clinical evidence. In contrast, in areas with no – or low quality – clinical evidence, we identified significant variety in management in between the centers: management of cytokine release syndrome, immune effector cell-related neurotoxicity syndrome, IgG substitution, autologous stem cell backups, anti-infective prophylaxis, and vaccinations. Conclusion: The results indicate the urgent need for better harmonization of supportive care in CAR-T cell therapies including clinical research to improve clinical outcome

    Human Practice. Digital Ecologies. Our Future. : 14. Internationale Tagung Wirtschaftsinformatik (WI 2019) : Tagungsband

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    Erschienen bei: universi - UniversitĂ€tsverlag Siegen. - ISBN: 978-3-96182-063-4Aus dem Inhalt: Track 1: Produktion & Cyber-Physische Systeme Requirements and a Meta Model for Exchanging Additive Manufacturing Capacities Service Systems, Smart Service Systems and Cyber- Physical Systems—What’s the difference? Towards a Unified Terminology Developing an Industrial IoT Platform – Trade-off between Horizontal and Vertical Approaches Machine Learning und Complex Event Processing: Effiziente Echtzeitauswertung am Beispiel Smart Factory Sensor retrofit for a coffee machine as condition monitoring and predictive maintenance use case Stakeholder-Analyse zum Einsatz IIoT-basierter Frischeinformationen in der Lebensmittelindustrie Towards a Framework for Predictive Maintenance Strategies in Mechanical Engineering - A Method-Oriented Literature Analysis Development of a matching platform for the requirement-oriented selection of cyber physical systems for SMEs Track 2: Logistic Analytics An Empirical Study of Customers’ Behavioral Intention to Use Ridepooling Services – An Extension of the Technology Acceptance Model Modeling Delay Propagation and Transmission in Railway Networks What is the impact of company specific adjustments on the acceptance and diffusion of logistic standards? Robust Route Planning in Intermodal Urban Traffic Track 3: Unternehmensmodellierung & Informationssystemgestaltung (Enterprise Modelling & Information Systems Design) Work System Modeling Method with Different Levels of Specificity and Rigor for Different Stakeholder Purposes Resolving Inconsistencies in Declarative Process Models based on Culpability Measurement Strategic Analysis in the Realm of Enterprise Modeling – On the Example of Blockchain-Based Initiatives for the Electricity Sector Zwischenbetriebliche Integration in der Möbelbranche: Konfigurationen und Einflussfaktoren Novices’ Quality Perceptions and the Acceptance of Process Modeling Grammars Entwicklung einer Definition fĂŒr Social Business Objects (SBO) zur Modellierung von Unternehmensinformationen Designing a Reference Model for Digital Product Configurators Terminology for Evolving Design Artifacts Business Role-Object Specification: A Language for Behavior-aware Structural Modeling of Business Objects Generating Smart Glasses-based Information Systems with BPMN4SGA: A BPMN Extension for Smart Glasses Applications Using Blockchain in Peer-to-Peer Carsharing to Build Trust in the Sharing Economy Testing in Big Data: An Architecture Pattern for a Development Environment for Innovative, Integrated and Robust Applications Track 4: Lern- und Wissensmanagement (e-Learning and Knowledge Management) eGovernment Competences revisited – A Literature Review on necessary Competences in a Digitalized Public Sector Say Hello to Your New Automated Tutor – A Structured Literature Review on Pedagogical Conversational Agents Teaching the Digital Transformation of Business Processes: Design of a Simulation Game for Information Systems Education Conceptualizing Immersion for Individual Learning in Virtual Reality Designing a Flipped Classroom Course – a Process Model The Influence of Risk-Taking on Knowledge Exchange and Combination Gamified Feedback durch Avatare im Mobile Learning Alexa, Can You Help Me Solve That Problem? - Understanding the Value of Smart Personal Assistants as Tutors for Complex Problem Tasks Track 5: Data Science & Business Analytics Matching with Bundle Preferences: Tradeoff between Fairness and Truthfulness Applied image recognition: guidelines for using deep learning models in practice Yield Prognosis for the Agrarian Management of Vineyards using Deep Learning for Object Counting Reading Between the Lines of Qualitative Data – How to Detect Hidden Structure Based on Codes Online Auctions with Dual-Threshold Algorithms: An Experimental Study and Practical Evaluation Design Features of Non-Financial Reward Programs for Online Reviews: Evaluation based on Google Maps Data Topic Embeddings – A New Approach to Classify Very Short Documents Based on Predefined Topics Leveraging Unstructured Image Data for Product Quality Improvement Decision Support for Real Estate Investors: Improving Real Estate Valuation with 3D City Models and Points of Interest Knowledge Discovery from CVs: A Topic Modeling Procedure Online Product Descriptions – Boost for your Sales? EntscheidungsunterstĂŒtzung durch historienbasierte Dienstreihenfolgeplanung mit Pattern A Semi-Automated Approach for Generating Online Review Templates Machine Learning goes Measure Management: Leveraging Anomaly Detection and Parts Search to Improve Product-Cost Optimization Bedeutung von Predictive Analytics fĂŒr den theoretischen Erkenntnisgewinn in der IS-Forschung Track 6: Digitale Transformation und Dienstleistungen Heuristic Theorizing in Software Development: Deriving Design Principles for Smart Glasses-based Systems Mirroring E-service for Brick and Mortar Retail: An Assessment and Survey Taxonomy of Digital Platforms: A Platform Architecture Perspective Value of Star Players in the Digital Age Local Shopping Platforms – Harnessing Locational Advantages for the Digital Transformation of Local Retail Outlets: A Content Analysis A Socio-Technical Approach to Manage Analytics-as-a-Service – Results of an Action Design Research Project Characterizing Approaches to Digital Transformation: Development of a Taxonomy of Digital Units Expectations vs. Reality – Benefits of Smart Services in the Field of Tension between Industry and Science Innovation Networks and Digital Innovation: How Organizations Use Innovation Networks in a Digitized Environment Characterising Social Reading Platforms— A Taxonomy-Based Approach to Structure the Field Less Complex than Expected – What Really Drives IT Consulting Value Modularity Canvas – A Framework for Visualizing Potentials of Service Modularity Towards a Conceptualization of Capabilities for Innovating Business Models in the Industrial Internet of Things A Taxonomy of Barriers to Digital Transformation Ambidexterity in Service Innovation Research: A Systematic Literature Review Design and success factors of an online solution for cross-pillar pension information Track 7: IT-Management und -Strategie A Frugal Support Structure for New Software Implementations in SMEs How to Structure a Company-wide Adoption of Big Data Analytics The Changing Roles of Innovation Actors and Organizational Antecedents in the Digital Age Bewertung des Kundennutzens von Chatbots fĂŒr den Einsatz im Servicedesk Understanding the Benefits of Agile Software Development in Regulated Environments Are Employees Following the Rules? On the Effectiveness of IT Consumerization Policies Agile and Attached: The Impact of Agile Practices on Agile Team Members’ Affective Organisational Commitment The Complexity Trap – Limits of IT Flexibility for Supporting Organizational Agility in Decentralized Organizations Platform Openness: A Systematic Literature Review and Avenues for Future Research Competence, Fashion and the Case of Blockchain The Digital Platform Otto.de: A Case Study of Growth, Complexity, and Generativity Track 8: eHealth & alternde Gesellschaft Security and Privacy of Personal Health Records in Cloud Computing Environments – An Experimental Exploration of the Impact of Storage Solutions and Data Breaches Patientenintegration durch Pfadsysteme Digitalisierung in der StressprĂ€vention – eine qualitative Interviewstudie zu Nutzenpotenzialen User Dynamics in Mental Health Forums – A Sentiment Analysis Perspective Intent and the Use of Wearables in the Workplace – A Model Development Understanding Patient Pathways in the Context of Integrated Health Care Services - Implications from a Scoping Review Understanding the Habitual Use of Wearable Activity Trackers On the Fit in Fitness Apps: Studying the Interaction of Motivational Affordances and Users’ Goal Orientations in Affecting the Benefits Gained Gamification in Health Behavior Change Support Systems - A Synthesis of Unintended Side Effects Investigating the Influence of Information Incongruity on Trust-Relations within Trilateral Healthcare Settings Track 9: Krisen- und KontinuitĂ€tsmanagement Potentiale von IKT beim Ausfall kritischer Infrastrukturen: Erwartungen, Informationsgewinnung und Mediennutzung der Zivilbevölkerung in Deutschland Fake News Perception in Germany: A Representative Study of People’s Attitudes and Approaches to Counteract Disinformation Analyzing the Potential of Graphical Building Information for Fire Emergency Responses: Findings from a Controlled Experiment Track 10: Human-Computer Interaction Towards a Taxonomy of Platforms for Conversational Agent Design Measuring Service Encounter Satisfaction with Customer Service Chatbots using Sentiment Analysis Self-Tracking and Gamification: Analyzing the Interplay of Motivations, Usage and Motivation Fulfillment Erfolgsfaktoren von Augmented-Reality-Applikationen: Analyse von Nutzerrezensionen mit dem Review-Mining-Verfahren Designing Dynamic Decision Support for Electronic Requirements Negotiations Who is Stressed by Using ICTs? A Qualitative Comparison Analysis with the Big Five Personality Traits to Understand Technostress Walking the Middle Path: How Medium Trade-Off Exposure Leads to Higher Consumer Satisfaction in Recommender Agents Theory-Based Affordances of Utilitarian, Hedonic and Dual-Purposed Technologies: A Literature Review Eliciting Customer Preferences for Shopping Companion Apps: A Service Quality Approach The Role of Early User Participation in Discovering Software – A Case Study from the Context of Smart Glasses The Fluidity of the Self-Concept as a Framework to Explain the Motivation to Play Video Games Heart over Heels? An Empirical Analysis of the Relationship between Emotions and Review Helpfulness for Experience and Credence Goods Track 11: Information Security and Information Privacy Unfolding Concerns about Augmented Reality Technologies: A Qualitative Analysis of User Perceptions To (Psychologically) Own Data is to Protect Data: How Psychological Ownership Determines Protective Behavior in a Work and Private Context Understanding Data Protection Regulations from a Data Management Perspective: A Capability-Based Approach to EU-GDPR On the Difficulties of Incentivizing Online Privacy through Transparency: A Qualitative Survey of the German Health Insurance Market What is Your Selfie Worth? A Field Study on Individuals’ Valuation of Personal Data Justification of Mass Surveillance: A Quantitative Study An Exploratory Study of Risk Perception for Data Disclosure to a Network of Firms Track 12: Umweltinformatik und nachhaltiges Wirtschaften KommunikationsfĂ€den im Nadelöhr – Fachliche Prozessmodellierung der Nachhaltigkeitskommunikation am Kapitalmarkt Potentiale und Herausforderungen der Materialflusskostenrechnung Computing Incentives for User-Based Relocation in Carsharing Sustainability’s Coming Home: Preliminary Design Principles for the Sustainable Smart District Substitution of hazardous chemical substances using Deep Learning and t-SNE A Hierarchy of DSMLs in Support of Product Life-Cycle Assessment A Survey of Smart Energy Services for Private Households Door-to-Door Mobility Integrators as Keystone Organizations of Smart Ecosystems: Resources and Value Co-Creation – A Literature Review Ein EntscheidungsunterstĂŒtzungssystem zur ökonomischen Bewertung von Mieterstrom auf Basis der Clusteranalyse Discovering Blockchain for Sustainable Product-Service Systems to enhance the Circular Economy Digitale RĂŒckverfolgbarkeit von Lebensmitteln: Eine verbraucherinformatische Studie Umweltbewusstsein durch audiovisuelles Content Marketing? Eine experimentelle Untersuchung zur Konsumentenbewertung nachhaltiger Smartphones Towards Predictive Energy Management in Information Systems: A Research Proposal A Web Browser-Based Application for Processing and Analyzing Material Flow Models using the MFCA Methodology Track 13: Digital Work - Social, mobile, smart On Conversational Agents in Information Systems Research: Analyzing the Past to Guide Future Work The Potential of Augmented Reality for Improving Occupational First Aid Prevent a Vicious Circle! The Role of Organizational IT-Capability in Attracting IT-affine Applicants Good, Bad, or Both? Conceptualization and Measurement of Ambivalent User Attitudes Towards AI A Case Study on Cross-Hierarchical Communication in Digital Work Environments ‘Show Me Your People Skills’ - Employing CEO Branding for Corporate Reputation Management in Social Media A Multiorganisational Study of the Drivers and Barriers of Enterprise Collaboration Systems-Enabled Change The More the Merrier? The Effect of Size of Core Team Subgroups on Success of Open Source Projects The Impact of Anthropomorphic and Functional Chatbot Design Features in Enterprise Collaboration Systems on User Acceptance Digital Feedback for Digital Work? Affordances and Constraints of a Feedback App at InsurCorp The Effect of Marker-less Augmented Reality on Task and Learning Performance Antecedents for Cyberloafing – A Literature Review Internal Crowd Work as a Source of Empowerment - An Empirical Analysis of the Perception of Employees in a Crowdtesting Project Track 14: GeschĂ€ftsmodelle und digitales Unternehmertum Dividing the ICO Jungle: Extracting and Evaluating Design Archetypes Capturing Value from Data: Exploring Factors Influencing Revenue Model Design for Data-Driven Services Understanding the Role of Data for Innovating Business Models: A System Dynamics Perspective Business Model Innovation and Stakeholder: Exploring Mechanisms and Outcomes of Value Creation and Destruction Business Models for Internet of Things Platforms: Empirical Development of a Taxonomy and Archetypes Revitalizing established Industrial Companies: State of the Art and Success Principles of Digital Corporate Incubators When 1+1 is Greater than 2: Concurrence of Additional Digital and Established Business Models within Companies Special Track 1: Student Track Investigating Personalized Price Discrimination of Textile-, Electronics- and General Stores in German Online Retail From Facets to a Universal Definition – An Analysis of IoT Usage in Retail Is the Technostress Creators Inventory Still an Up-To-Date Measurement Instrument? Results of a Large-Scale Interview Study Application of Media Synchronicity Theory to Creative Tasks in Virtual Teams Using the Example of Design Thinking TrustyTweet: An Indicator-based Browser-Plugin to Assist Users in Dealing with Fake News on Twitter Application of Process Mining Techniques to Support Maintenance-Related Objectives How Voice Can Change Customer Satisfaction: A Comparative Analysis between E-Commerce and Voice Commerce Business Process Compliance and Blockchain: How Does the Ethereum Blockchain Address Challenges of Business Process Compliance? Improving Business Model Configuration through a Question-based Approach The Influence of Situational Factors and Gamification on Intrinsic Motivation and Learning Evaluation von ITSM-Tools fĂŒr Integration und Management von Cloud-Diensten am Beispiel von ServiceNow How Software Promotes the Integration of Sustainability in Business Process Management Criteria Catalog for Industrial IoT Platforms from the Perspective of the Machine Tool Industry Special Track 3: Demos & Prototyping Privacy-friendly User Location Tracking with Smart Devices: The BeaT Prototype Application-oriented robotics in nursing homes Augmented Reality for Set-up Processe Mixed Reality for supporting Remote-Meetings Gamification zur Motivationssteigerung von Werkern bei der Betriebsdatenerfassung Automatically Extracting and Analyzing Customer Needs from Twitter: A “Needmining” Prototype GaNEsHA: Opportunities for Sustainable Transportation in Smart Cities TUCANA: A platform for using local processing power of edge devices for building data-driven services Demonstrator zur Beschreibung und Visualisierung einer kritischen Infrastruktur Entwicklung einer alltagsnahen persuasiven App zur Bewegungsmotivation fĂŒr Ă€ltere Nutzerinnen und Nutzer A browser-based modeling tool for studying the learning of conceptual modeling based on a multi-modal data collection approach Exergames & Dementia: An interactive System for People with Dementia and their Care-Network Workshops Workshop Ethics and Morality in Business Informatics (Workshop Ethik und Moral in der Wirtschaftsinformatik – EMoWI’19) Model-Based Compliance in Information Systems - Foundations, Case Description and Data Set of the MobIS-Challenge for Students and Doctoral Candidates Report of the Workshop on Concepts and Methods of Identifying Digital Potentials in Information Management Control of Systemic Risks in Global Networks - A Grand Challenge to Information Systems Research Die Mitarbeiter von morgen - Kompetenzen kĂŒnftiger Mitarbeiter im Bereich Business Analytics Digitaler Konsum: Herausforderungen und Chancen der Verbraucherinformati

    MĂ©canismes rĂ©actionnels d’activation et de rĂ©duction catalytique du CO₂

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    L’utilisation du dioxyde de carbone (CO₂) comme source de composĂ©s C1 pour la chimie fine est intĂ©ressante d’un point de vue Ă©conomique et pour des raisons Ă©cologiques. Issu de l’oxydation de la matiĂšre carbonĂ©e, le CO₂ est un gaz non-toxique, abondant et peu coĂ»teux. Sa transformation en produits chimiques prĂ©sentant de hautes valeurs ajoutĂ©es est actuellement entravĂ©e par sa stabilitĂ© thermodynamique. Afin de dĂ©velopper de nouveaux processus et catalyseurs pour la rĂ©duction catalytique du CO₂, une comprĂ©hension dĂ©taillĂ©e des mĂ©canismes rĂ©actionnels de l’activation et de la rĂ©duction de ce gaz est nĂ©cessaire. En utilisant comme catalyseurs des paires de Lewis frustrĂ©e (FLPs) contenant une base azotĂ©e liĂ©e Ă  un ion silicĂ©nium, les influences respectives de l’adduit CO₂-FLP et du rĂ©ducteur ont Ă©tĂ© dĂ©terminĂ©es expĂ©rimentalement et par calcul DFT dans le cadre de l’hydroboration du CO₂ en Ă©quivalent de mĂ©thanol. Une nouvelle rĂ©action visant Ă  la crĂ©ation de liaisons carbone–carbone par le transfert du fragment pyridyle de molĂ©cules de pyridylsilanes (C₅H₄N–SiMe₃) sur le CO₂ Ă©tait Ă©galement Ă©tudiĂ©e. Le mĂ©canisme rĂ©actionnel de cette transformation a Ă©tĂ© Ă©tabli sur la base de calculs thĂ©oriques. Nous avons montrĂ© le double rĂŽle du CO₂ qui est Ă  la fois un rĂ©actif et un catalyseur de la rĂ©action de transfert du groupe pyridyle. La comprĂ©hension fine de cette rĂ©action nous a permis de l’étendre Ă  la formation de sulfones et sulfonamides qui sont des groupements chimiques essentiels dans le domaine pharmaceutique. En utilisant le SO₂ Ă  la fois comme catalyseur et rĂ©actif, des silanes aromatiques et hĂ©tĂ©ro-aromatiques ont Ă©tĂ© transformĂ©s en sulfones correspondants en une seule Ă©tape. Finalement, nous avons trouvĂ© un couplage croisĂ© original, de type Hiyama, entre espĂšces aromatiques Ă©lectrophiles et des espĂšces C(sp2)–Si nuclĂ©ophiles en prĂ©sence de SO₂.The use of CO₂ as a C1 chemical feedstock for the fine chemical industry is interesting both economically and ecologically, as CO₂ is non-toxic, abundant and cheap. Nevertheless, transformations of CO₂ into value-added products is hampered by its high thermodynamic stability and its inertness toward reduction. In order to design new catalysts able to overcome this kinetic challenge, a profound understanding of the reaction mechanisms at play in CO₂ reduction is needed. Using novel N/Si+ frustrated Lewis pairs (FLPs), the influence of CO₂ adducts and different hydroborane reducing agents on the reaction mechanism in the catalytic hydroboration of CO₂ were investigated, both by DFT calculations and experiments. In a second step, the reaction mechanism of a novel reaction for the creation of C–C bonds from CO₂ and pyridylsilanes (C₅H₄N–SiMe₃) was analyzed by DFT calculations. It was shown that CO₂ plays a double role in this transformation, acting both as a catalyst and a C1-building block. The fine understanding of this transformation then led to the development of a novel approach for the synthesis of sulfones and sulfonamides. Starting from SO₂ and aromatic silanes/amine silanes, these products were obtained in a single step under metal-free conditions. Noteworthy, sulfones and sulfonamides are common motifs in organic chemistry and found in a variety of highly important drugs. Finally, this concept was extended to aromatic halides as coupling partners, and it was thus shown for the first time that a sulfonylative Hiyama reaction is a possible approach to the synthesis of sulfones

    Reaction mechanisms of CO2_2 activation and catalytic reduction

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    Reaction mechanisms of CO2_2 activation and catalytic reduction

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    Merging Electrocatalytic Alcohol Oxidation with C-N Bond Formation by Electrifying Metal-Ligand Cooperative Catalysts

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    The development of energy and atom efficiency processes is thought to play an important role for a sustainable chemical industry of the future. One opportunity could be the electrification of thermal processes to benefit from the inherent advantages of electrochemistry, such as safety, scalability, a cheap and traceless redox agent (electrons), and the possibility to directly control the energy input of a given reaction via the applied potential. Molecular electrocatalytic alcohol oxidation emerged as a powerful tool for energy efficient redox transformations with possible applications in both green synthesis and energy-relevant domains. Using transfer hydrogenation catalysts under electrochemical conditions was shown to be promising avenue in this respect, but is today limited in terms of substrate scope. Here, we reported the electrification of acceptor-less dehydrogenation catalysts for the coupling of alcohol oxidation with C-N bond formation. Imines are thus obtained with excellent selectivity and faradaic efficiency, showing a possibility route towards added-value products from simple building blocks. We hope that the successful electrification of such atom-efficient systems can contribute to a more energy efficient organic redox chemistry

    Valorization of small molecules: from mechanisms to new reactions

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    Synthesis of Aromatic Sulfones from SO2_2 and Organosilanes, under Metal-free Conditions

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    International audienceThe sulfone functional group (RSO2R?) has found widespread applications in organic chemistry, due to its unique physico-chemical properties (stability, lipophilicity, H-bonding etc.) and many aryl-or heteroarylsulfones derivatives are currently exploited as drugs (e.g. bicalutamide, eletriptan and Vioxx) or herbicides. The presence of these structural motifs in pharmaceuticals asks for mild and step efficient synthesis methodologies. Classical synthetic routes to aryl-or heteroarylsulfones generally comprise the oxidation of sulfides or the sulfonylation of arenes with toxics reagents under harsh conditions. Recently several examples of sulfinate salts coupling leading to sulfones under mild conditions have been developed. These methods however require two steps with the use of strong nucleophiles such as organomagnesium or organolithium reagents. In 2013, Shavnya et al. reported the one step reaction using milder nucleophiles such as organoborron reagents, but transition metals catalysts are necessary (Scheme 1). Among available nucleophiles, organosilanes are stable, easy to prepare and to handle and non-toxic. Their use might require activation by fluoride or alkoxide salts. We herein report the one-step, metal free, synthesis of aryl and heteroarylsulfones from silanes, SO2_2 and an alkylhalide, using fluoride anions as promotors at room temperature (scheme 2). Computational studies allowed proposing a mechanism and elucidating the experimentally observed difference in reactivity especially between pyridyl and phenyl silane derivatives, by highlighting the triple catalytic role of SO2_2
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