Visible Light Photocatalysis in Organic Chemistry

Filling the need for a ready reference that reflects the vast developments in this field, this book presents everything from fundamentals, applications, various reaction types, and technical applications. Edited by rising stars in the scientific community, the text focuses solely on visible light photocatalysis in the context of organic chemistry. This primarily entails photoinduced electron transfer and energy transfer chemistry sensitized by polypyridyl complexes, yet also includes the use of organic dyes and heterogeneous catalysts. A valuable resource to the synthetic organic community, polymer and medicinal chemists, as well as industry professionals.

Autorentext
Corey R. J. Stephenson is Professor at University of Michigan. He received his undergraduate degree in chemistry at the University of Waterloo, followed by his PhD at the University of Pittsburgh. After post-doctoral studies at the ETH in Zurich, Switzerland, he worked at the Department of Chemistry at Boston University, before joining University of Michigan.

Tehshik P. Yoon is Professor at the University of Wisconsin-Madison. After his graduate studies at Harvard University, he finished his PhD under the guidance of Prof. MacMillan at Caltech, Pasadena and was postdoctoral fellow in the group of Eric Jacobsen at Harvard.

David W. C. MacMillan is Professor at Princeton University. He received his undergraduate degree in chemistry at the University of Glasgow, followed by a PhD at the University of California, Irvine, before undertaking a postdoctoral position at Harvard University. He began his independent career at University of California, Berkeley in 1998 before moving to Caltech in 2000. In 2006, he became James S. McDonnell Distinguished University Professor at Princeton University, where he served as Department Chair from 2010-15.

Inhalt

**1 An Overview of the Physical and Photophysical Properties of [Ru(bpy)3]2+ 1
**DanielaM. Arias-Rotondo and James K. McCusker

1.1 Introduction 1

1.2 [Ru(bpy)3]2+: Optical and Electrochemical Properties 4

1.2.1 Optical Properties 4

1.2.2 Electrochemical Properties 6

1.3 Excited State Kinetics 8

1.3.1 Steady-State Emission 8

1.3.2 Time-Resolved Emission 10

1.4 Excited-State Reactivity of [Ru(bpy)3]2+ 11

1.5 Energy Transfer: Förster and Dexter Mechanisms 12

1.6 Electron Transfer 14

1.7 Probing the Mechanism, Stage I: SternVolmer Quenching Studies 14

1.8 Probing the Mechanism, Stage II: Electron Versus Energy Transfer 16

1.9 Designing Photocatalysts: [Ru(bpy)3]2+ as a Starting Point 20

1.10 Conclusion 22

References 23

**2 Visible-Light-Mediated Free Radical Synthesis 25
**Louis Fensterbank, Jean-Philippe Goddard, and Cyril Ollivier

2.1 Introduction 25

2.2 Basics of the Photocatalytic Cycle 26

2.3 Generation of Radicals 27

2.3.1 Formation of C-Centered Radicals 27

2.3.1.1 Dehalogenation (I, Br, Cl) 27

2.3.1.2 Other C-Heteroatom Cleavage 29

2.3.1.3 CC Bond Cleavage 29

2.3.2 Formation of N-Centered Radicals 30

2.4 CX Bond Formation 30

2.4.1 CO Bond 30

2.4.2 CN Bond 32

2.4.3 CS and CSe Bonds 33

2.4.4 CBr Bond 34

2.4.5 CF Bond 34

2.4.6 CB Bond 35

2.5 CC Bond Formation 35

2.5.1 Formation and Reactivity of Aryl Radicals 35

2.5.2 Formation and Reactivity of Trifluoromethyl and Related Radicals 40

2.5.2.1 Photocatalyzed Reduction of Perfluorohalogen Derivatives 40

2.5.2.2 Photocatalyzed Reduction of Perfluoroalkyl-Substituted Onium Salts 42

2.5.2.3 Photocatalyzed Formation of Perfluoroalkyl Radicals from Sulfonyl and Sulfinyl Derivatives 43

2.5.3 Formation and Reactivity of Alkyl and Related Radicals 45

2.5.3.1 CC Bond FormationThrough Photocatalyzed Reduction of Halogen Derivatives and Analogs 45

2.5.3.2 CC Bond FormationThrough Photocatalyzed Oxidation of Electron-Rich Functional Group 47

2.5.3.3 CC Bond FormationThrough Photocatalyzed Oxidation of Amino Group 48

2.6 Radical Cascade Applications 49

2.6.1 Intramolecular Polycyclization Processes 49

2.6.2 Sequential Inter- and Intramolecular Processes 51

2.6.3 Sequential Radical and Polar Processes 56

References 59

**3 AtomTransfer Radical Addition using Photoredox Catalysis 73
**Theresa M.Williams and Corey R. J. Stephenson

3.1 Introduction 73

3.2 Transition Metal-Catalyzed ATRA 77

3.2.1 Ruthenium- and Iridium-Based ATRA 77

3.2.1.1 Mechanistic Investigations 77

3.2.1.2 Ruthenium- and Iridium-Based ATRA 80

3.2.2 Copper-Mediated ATRA 81

3.2.2.1 Trifluoromethylation 82

3.3 Other Photocatalysts for ATRA Transformations 84

3.3.1 p-Anisaldehyde 84

3.4 Semiconductor 86

3.5 Atom Transfer Radical Cyclization (ATRC) 87

3.6 Atom Transfer Radical Polymerization (ATRP) 89

3.7 Conclusion 90

References 90

4 Visible Light Mediated -Amino CH Functionalization Reactions 93
**You-Quan Zou andWen-Jing Xiao

4.1 Introduction 93

4.2 Visible Light Mediated -Amino CH Functionalization Via Iminium Ions 95

4.2.1 Aza-Henry Reaction 95

4.2.2 Mannich Reaction 100

4.2.3 Strecker Reaction 104

4.2.4 FriedelCrafts Reaction 105

4.2.5 Alkynylation Reaction 108

4.2.6 Phosphonation Reaction 109

4.2.7 Addition of 1,3-Dicarbonyls 109

4.2.8 Formation of CN and CO Bonds 110

4.2.9 Miscellaneous 112

4.3 Visible Light Mediated -Amino CH Functionalization Via -Amino Radicals 116 4.3.1...