Photochemical and Electrochemical Activation Strategies of C(sp3)-Based Building Blocks for Organic Synthesis (Springer Theses)

This book addresses novel C(sp3)-C(sp2) and C(sp3)-heteroatom bond-forming reactions. Two strategies are given in the book using photoredox or electrochemical methods. The first strategy describes that the hydroalkylation of alkynes via photoredox-mediated Ni/Ir dual catalysis produces trisubstituted alkenes as versatile synthetic building blocks for the synthesis of pharmaceutical agents and natural products. High regioselectivity and E/Z-selectivity were achieved by introducing silyl groups that can provide steric and electronic effects to these selectivities with extensive opportunities for post-functionalization. The second strategy enables the development of C(sp3)-heteroatom bond-forming reactions through the electrochemical activation of C(sp3)-B bonds. The bonding of heteroatoms to carbon atoms has been an enduring subject of investigation for organic chemists. The function of most molecules is mainly determined by heteroatoms attached to the carbon atom, althoughthe backbone structure of organic compounds comprises carbon fragments. Cover Springer Theses Series Photochemical and Electrochemical Activation Strategies of C(sp3)-Based Building Blocks for Organic Synthesis Copyright Supervisor’s Foreword Preface Contributions Acknowledgments Contents List of Figures List of Schemes List of Tables Part I. C(sp2)–C(sp3) Bond Formation Reactions Enabled by Photoredox/Nickel Dual Catalysis 1. The Key Concepts and Strategy in Photoredox/Nickel Dual Catalysis and Application to C–C Bond Formation Reactions 1.1 Introduction 1.2 Key Concepts in Visible Light Photoredox Catalysis 1.3 Principles of Photoredox/Nickel Dual Catalysis 1.4 Photocatalytic C–H Activation and the Role of Chlorine Radicals 1.5 Conclusion References 2. Highly Regioselective and E/Z‐Selective Hydroalkylation of Alkyne via Photoredox-Mediated Ni/Ir Dual Catalysis 2.1 Introduction 2.2 Results and Discussion 2.2.1 Optimization of Reaction Conditions 2.2.2 Substrate Scope 2.2.3 Post-Functionalization and Mechanistic Studies 2.3 Conclusion 2.4 Experimental Section 2.4.1 General Information 2.4.2 Substrate Preparation 2.4.3 Reaction Optimization 2.4.4 Identification of α/β- and E/Z Configuration of Products 2.4.5 General Procedure for the Hydroalkylation of Activated Alkynes 2.4.6 A Representative 1 mmol Scale Reaction 2.4.7 Post-Functionalization of Enone Products 2.4.8 Radical Quenching Study Using TEMPO 2.4.9 Investigation of Regioselectivity Dependence on the Size of Coupling Partner 2.4.10 Investigation of a Base Effect 2.4.11 Alkenylation Test of THF Radicals by DTBP 2.4.12 Deuterium Labeling Study References Part II. Development of C(sp3)–Heteroatom Bond-Forming Reactions via Electrochemical Activation of C(sp3)–B Bonds and Follow-Up Projects 3. Recent Achievements of C(sp3)‒Heteroatom Bond Formation in Electroorganic Synthesis and History of C(sp3)‒B Bond Activation 3.1 Introduction 3.2 Advances in the Merger of Electrochemistry and Organic Synthesis 3.2.1 Introduction of Electrosynthesis 3.2.2 Representative Electrocatalytic Reactions 3.3 History of C(sp3)−B Bond Activation 3.4 Conclusion References 4. Introduction of Heteroatoms to Alkyl Carbocations Generated from Alkylboron Reagents via Electrochemical Activation 4.1 Introduction 4.2 Results and Discussion 4.3 Conclusion 4.4 Experimental Section 4.4.1 General Information 4.4.2 Substrate Preparation 4.4.3 Electrochemical Analyses for Reaction Design 4.4.4 Reaction Optimization 4.4.5 General Procedure for Electrochemical C(sp3)–Heteroatom Bond Formation 4.4.6 Representative Larger Scale Reactions 4.4.7 Experimental Procedure for Electrochemical Bond Formation via In Situ Generation of Reactive Precursor 4.4.8 Divided Cell Experiments 4.4.9 Constant Potential Electrolysis 4.4.10 Mechanistic Probes and Kinetic Study 4.4.11 Experimental Procedures and Characterization Data 4.4.12 Unsuitable Trifluoroborate Substrates and Heteroatom Nucleophiles 4.4.13 X-Ray of Compound of (11S)-87 References This book addresses novel C(sp3)-C(sp2) and C(sp3)-heteroatom bond-forming reactions. Two strategies are given in the book using photoredox or electrochemical methods. The first strategy describes that the hydroalkylation of alkynes via photoredox-mediated Ni/Ir dual catalysis produces trisubstituted alkenes as versatile synthetic building blocks for the synthesis of pharmaceutical agents and natural products. High regioselectivity and E/Z-selectivity were achieved by introducing silyl groups that can provide steric and electronic effects to these selectivities with extensive opportunities for post-functionalization. The second strategy enables the development of C(sp3)-heteroatom bond-forming reactions through the electrochemical activation of C(sp3)-B bonds. The bonding of heteroatoms to carbon atoms has been an enduring subject of investigation for organic chemists. The function of most molecules is mainly determined by heteroatomsattached to the carbon atom, although the backbone structure of organic compounds comprises carbon fragments.