<p><b>1 An Overview of the Physical and Photophysical Properties of [Ru(bpy)3]2+ 1<br /></b><i>DanielaM. Arias-Rotondo and James K. McCusker</i></p> <p>1.1 Introduction 1</p> <p>1.2 [Ru(bpy)3]2+: Optical and Electrochemical Properties 4</p> <p>1.2.1 Optical Properties 4</p> <p>1.2.2 Electrochemical Properties 6</p> <p>1.3 Excited State Kinetics 8</p> <p>1.3.1 Steady-State Emission 8</p> <p>1.3.2 Time-Resolved Emission 10</p> <p>1.4 Excited-State Reactivity of [Ru(bpy)3]2+ 11</p> <p>1.5 Energy Transfer: Förster and Dexter Mechanisms 12</p> <p>1.6 Electron Transfer 14</p> <p>1.7 Probing the Mechanism, Stage I: Stern–Volmer Quenching Studies 14</p> <p>1.8 Probing the Mechanism, Stage II: Electron Versus Energy Transfer 16</p> <p>1.9 Designing Photocatalysts: [Ru(bpy)3]2+ as a Starting Point 20</p> <p>1.10 Conclusion 22</p> <p>References 23</p> <p><b>2 Visible-Light-Mediated Free Radical Synthesis 25<br /></b><i>Louis Fensterbank, Jean-Philippe Goddard, and Cyril Ollivier</i></p> <p>2.1 Introduction 25</p> <p>2.2 Basics of the Photocatalytic Cycle 26</p> <p>2.3 Generation of Radicals 27</p> <p>2.3.1 Formation of C-Centered Radicals 27</p> <p>2.3.1.1 Dehalogenation (I, Br, Cl) 27</p> <p>2.3.1.2 Other C-Heteroatom Cleavage 29</p> <p>2.3.1.3 C—C Bond Cleavage 29</p> <p>2.3.2 Formation of N-Centered Radicals 30</p> <p>2.4 C—X Bond Formation 30</p> <p>2.4.1 C—O Bond 30</p> <p>2.4.2 C—N Bond 32</p> <p>2.4.3 C—S and C—Se Bonds 33</p> <p>2.4.4 C—Br Bond 34</p> <p>2.4.5 C—F Bond 34</p> <p>2.4.6 C—B Bond 35</p> <p>2.5 C—C Bond Formation 35</p> <p>2.5.1 Formation and Reactivity of Aryl Radicals 35</p> <p>2.5.2 Formation and Reactivity of Trifluoromethyl and Related Radicals 40</p> <p>2.5.2.1 Photocatalyzed Reduction of Perfluorohalogen Derivatives 40</p> <p>2.5.2.2 Photocatalyzed Reduction of Perfluoroalkyl-Substituted Onium Salts 42</p> <p>2.5.2.3 Photocatalyzed Formation of Perfluoroalkyl Radicals from Sulfonyl and Sulfinyl Derivatives 43</p> <p>2.5.3 Formation and Reactivity of Alkyl and Related Radicals 45</p> <p>2.5.3.1 C—C Bond FormationThrough Photocatalyzed Reduction of Halogen Derivatives and Analogs 45</p> <p>2.5.3.2 C—C Bond FormationThrough Photocatalyzed Oxidation of Electron-Rich Functional Group 47</p> <p>2.5.3.3 C—C Bond FormationThrough Photocatalyzed Oxidation of Amino Group 48</p> <p>2.6 Radical Cascade Applications 49</p> <p>2.6.1 Intramolecular Polycyclization Processes 49</p> <p>2.6.2 Sequential Inter- and Intramolecular Processes 51</p> <p>2.6.3 Sequential Radical and Polar Processes 56</p> <p>References 59</p> <p><b>3 AtomTransfer Radical Addition using Photoredox Catalysis 73<br /></b><i>Theresa M.Williams and Corey R. J. Stephenson</i></p> <p>3.1 Introduction 73</p> <p>3.2 Transition Metal-Catalyzed ATRA 77</p> <p>3.2.1 Ruthenium- and Iridium-Based ATRA 77</p> <p>3.2.1.1 Mechanistic Investigations 77</p> <p>3.2.1.2 Ruthenium- and Iridium-Based ATRA 80</p> <p>3.2.2 Copper-Mediated ATRA 81</p> <p>3.2.2.1 Trifluoromethylation 82</p> <p>3.3 Other Photocatalysts for ATRA Transformations 84</p> <p>3.3.1 p-Anisaldehyde 84</p> <p>3.4 Semiconductor 86</p> <p>3.5 Atom Transfer Radical Cyclization (ATRC) 87</p> <p>3.6 Atom Transfer Radical Polymerization (ATRP) 89</p> <p>3.7 Conclusion 90</p> <p>References 90</p> <p><b>4 Visible Light Mediated </b><b>;;-Amino C—H Functionalization Reactions 93<br /></b><i>You-Quan Zou andWen-Jing Xiao</i></p> <p>4.1 Introduction 93</p> <p>4.2 Visible Light Mediated α-Amino C—H Functionalization Via Iminium Ions 95</p> <p>4.2.1 Aza-Henry Reaction 95</p> <p>4.2.2 Mannich Reaction 100</p> <p>4.2.3 Strecker Reaction 104</p> <p>4.2.4 Friedel–Crafts Reaction 105</p> <p>4.2.5 Alkynylation Reaction 108</p> <p>4.2.6 Phosphonation Reaction 109</p> <p>4.2.7 Addition of 1,3-Dicarbonyls 109</p> <p>4.2.8 Formation of C—N and C—O Bonds 110</p> <p>4.2.9 Miscellaneous 112</p> <p>4.3 Visible Light Mediated α-Amino C—H Functionalization Via α-Amino Radicals 116</p> <p>4.3.1 Addition to Electron-Deficient Aromatics 116</p> <p>4.3.2 Addition to Electron-Deficient Alkenes 116</p> <p>4.3.3 Miscellaneous 120</p> <p>4.4 Conclusions and Perspectives 121</p> <p>References 122</p> <p><b>5 Visible Light Mediated Cycloaddition Reactions 129<br /></b><i>Scott Morris, Theresa Nguyen, and Nan Zheng</i></p> <p>5.1 Introduction 129</p> <p>5.2 [2+2] Cycloadditions: Formation of Four-Membered Rings 130</p> <p>5.2.1 Introduction to [2+2] Cycloadditions 130</p> <p>5.2.2 Utilization of the Reductive Quenching Cycle 130</p> <p>5.2.3 Utilization of the Oxidative Quenching Cycle 135</p> <p>5.2.4 Utilization of Energy Transfer 139</p> <p>5.2.5 [2+2] Conclusion 142</p> <p>5.3 [3+2] Cycloadditions: Formation of Five-Membered Rings 143</p> <p>5.3.1 Introduction to [3+2] Cycloadditions 143</p> <p>5.3.2 [3+2] Cycloaddition of Cyclopropylamines 143</p> <p>5.3.3 1,3-Dipolar Cycloaddition of Azomethine Ylides 145</p> <p>5.3.4 [3+2] Cycloaddition of Aryl Cyclopropyl Ketones 146</p> <p>5.3.5 [3+2] Cycloaddition via ATRA/ATRC 146</p> <p>5.3.6 [3+2] Conclusion 148</p> <p>5.4 [4+2] Cycloadditions: Formation of Six-Membered Rings 149</p> <p>5.4.1 Introduction to [4+2] Cycloadditions 149</p> <p>5.4.2 [4+2] Cycloadditions Using Radical Anions 149</p> <p>5.4.3 [4+2] Cycloadditions Using Radical Cations 151</p> <p>5.4.4 [4+2] Conclusion 154</p> <p>5.5 Conclusion 155</p> <p>References 156</p> <p><b>6 Metal-Free Photo(redox) Catalysis 159<br /></b><i>Kirsten Zeitler</i></p> <p>6.1 Introduction 159</p> <p>6.1.1 Background 162</p> <p>6.1.2 Classes of Organic Photocatalysts 162</p> <p>6.2 Applications of Organic Photocatalysts 166</p> <p>6.2.1 Energy Transfer Reactions 166</p> <p>6.2.2 Reductive Quenching of the Catalyst 171</p> <p>6.2.2.1 Cyanoarenes 171</p> <p>6.2.2.2 Quinones 172</p> <p>6.2.2.3 Cationic Dyes: Pyrylium, Quinolinium, and Acridinium Scaffolds 173</p> <p>6.2.2.4 Xanthene Dyes and Further Aromatic Scaffolds 188</p> <p>6.2.3 Oxidative Quenching of the Catalyst 203</p> <p>6.2.4 New Developments 214</p> <p>6.2.4.1 Upconversion 215</p> <p>6.2.4.2 Consecutive Photoelectron Transfer 215</p> <p>6.2.4.3 Multicatalysis 216</p> <p>6.3 Conclusion and Outlook 224</p> <p>References 224</p> <p><b>7 Visible Light and Copper Complexes: A Promising Match in Photoredox Catalysis 233<br /></b><i>Suva Paria and Oliver Reiser</i></p> <p>7.1 Introduction 233</p> <p>7.2 Photophysical Properties of Copper Catalysts 234</p> <p>7.3 Application of Copper Based Photocatalysts in Organic Synthesis 237</p> <p>7.4 Outlook 247</p> <p>Acknowledgment 248</p> <p>References 248</p> <p><b>8 Arene Functionalization by Visible Light Photoredox Catalysis 253<br /></b><i>Durga Hari Prasad, Thea Hering, and Burkhard König</i></p> <p>8.1 Introduction 253</p> <p>8.1.1 Aryl Diazonium Salts 253</p> <p>8.1.2 Diaryl Iodonium Salts 268</p> <p>8.1.3 Triaryl Sulfonium Salts 272</p> <p>8.1.4 Aryl Sulfonyl Chlorides 273</p> <p>8.2 Applications of Aryl Diazonium Salts 274</p> <p>8.3 Photoinduced Ullmann C—N Coupling 276</p> <p>8.4 Conclusion 278</p> <p>References 278</p> <p><b>9 Visible-Light Photocatalysis in the Synthesis of Natural Products 283<br /></b><i>Gregory L. Lackner, KyleW. Quasdorf, and Larry E. Overman</i></p> <p>References 295</p> <p><b>10 Dual Photoredox Catalysis: TheMerger of Photoredox Catalysis with Other Catalytic Activation Modes 299</b><br /><i>Christopher K. Prier and DavidW. C. MacMillan</i></p> <p>10.1 Introduction 299</p> <p>10.2 Merger of Photoredox Catalysis with Organocatalysis 300</p> <p>10.3 Merger of Photoredox Catalysis with Acid Catalysis 314</p> <p>10.3.1 Photoredox Catalysis and Brønsted Acid Catalysis 314</p> <p>10.3.2 Photoredox Catalysis and Lewis Acid Catalysis 318</p> <p>10.4 Merger of Photoredox Catalysis with Transition Metal Catalysis 320</p> <p>10.5 Conclusions 328</p> <p>References 328</p> <p><b>11 Enantioselective Photocatalysis 335<br /></b><i>Susannah C. Coote and Thorsten Bach</i></p> <p>11.1 Introduction 335</p> <p>11.2 The Twentieth Century: PioneeringWork 336</p> <p>11.3 The Twenty-First Century: Contemporary Developments 341</p> <p>11.3.1 Large-Molecule Chiral Hosts 341</p> <p>11.3.2 Small-Molecule Chiral Photosensitizers 343</p> <p>11.3.3 Lewis Acid-Mediated Photoreactions 353</p> <p>11.4 Conclusions and Outlook 357</p> <p>References 358</p> <p><b>12 Photomediated Controlled Polymerizations 363<br /></b><i>Nicolas J. Treat, Brett P. Fors, and Craig J. Hawker</i></p> <p>12.1 Catalyst Activation by Light 365</p> <p>12.1.1 Cu-Catalyzed Photoregulated Atom Transfer Radical Polymerizations (photoATRP) 365</p> <p>12.1.2 Photomediated ATRP with Non-Copper-Based Catalyst Systems 368</p> <p>12.1.3 Iodine-Mediated Photopolymerizations 371</p> <p>12.1.4 Metal-Free Photomediated Ring-Opening Metathesis Polymerization 375</p> <p>12.1.5 Photoregulated Reversible-Addition Fragmentation Chain Transfer Polymerizations (photoRAFT) 376</p> <p>12.2 Chain-End Activation by Light 383</p> <p>12.3 Conclusions 384</p> <p>References 385</p> <p><b>13 Accelerating Visible-Light Photoredox Catalysis in Continuous-Flow Reactors 389<br /></b><i>Natan J.W. Straathof and Timothy Noël</i></p> <p>13.1 Introduction 389</p> <p>13.2 Homogeneous Photocatalysis in Single-Phase Flow 392</p> <p>13.3 Gas–liquid Photocatalysis in Flow 401</p> <p>13.4 Heterogeneous Photocatalysis in Flow 408</p> <p>13.5 Conclusions 410</p> <p>Conflict of Interest 410</p> <p>References 410</p> <p><b>14 The Application of Visible-Light-Mediated Reactions to the Synthesis of Pharmaceutical Compounds 415<br /></b><i>James. J. Douglas</i></p> <p>14.1 Introduction 415</p> <p>14.2 Asymmetric Benzylation 415</p> <p>14.3 Amide Bond Formation 416</p> <p>14.4 C—H Azidation 417</p> <p>14.5 Visible-Light-Mediated Benzothiophene Synthesis 418</p> <p>14.6 α-Amino Radical Functionalization 419</p> <p>14.7 Visible-Light-Mediated Radical Smiles Rearrangement 422</p> <p>14.8 Photoredox and Nickel Dual Catalysis 423</p> <p>14.9 The Scale-Up of Visible-Light-Mediated Reactions Via Continuous</p> <p>Processing 426</p> <p>References 428</p> <p>Index 431</p>