Ligand Design in Metal Chemistry

The design of ancillary ligands used to modify the structural and reactivity properties of metal complexes has evolved into a rapidly expanding sub-discipline in inorganic and organometallic chemistry. Ancillary ligand design has figured directly in the discovery of new bonding motifs and stoichiometric reactivity, as well as in the development of new catalytic protocols that have had widespread positive impact on chemical synthesis on benchtop and industrial scales.

Ligand Design in Metal Chemistry presents a collection of cutting-edge contributions from leaders in the field of ligand design, encompassing a broad spectrum of ancillary ligand classes and reactivity applications. Topics covered include:

• Key concepts in ligand design

• Redox non-innocent ligands

• Ligands for selective alkene metathesis

• Ligands in cross-coupling

• Ligand design in polymerization

• Ligand design in modern lanthanide chemistry

• Cooperative metal-ligand reactivity

• P,N Ligands for enantioselective hydrogenation

• Spiro-cyclic ligands in asymmetric catalysis

This book will be a valuable reference for academic researchers and industry practitioners working in the field of ligand design, as well as those who work in the many areas in which the impact of ancillary ligand design has proven significant, for example synthetic organic chemistry, catalysis, medicinal chemistry, polymer science and materials chemistry.

Auteur

Mark Stradiotto, Department of Chemistry, Dalhousie University, Canada
Rylan Lundgren, Department of Chemistry, University of Alberta, Canada
Both professors have a well-established track-record of working in the field of organometallic ligand design and catalysis, and have published extensively on the subjects of metal-catalyzed cross-coupling, novel transition-metal bond activation, and asymmetric catalysis. They are co-inventors of the now commercialized DalPhos ligand family and have broad experience of the field of ligand design. Professor Stradiotto has worked in the field of organometallic chemistry for the past fourteen years. Professor Lundgren earned his PhD under the supervision of Prof Stradiotto at Dalhousie University in 2010. Following a PDF at MIT and Caltech with Prof. Greg Fu, Rylan accepted a faculty position at the University of Alberta (Canada).

Contenu

List of Contributors xii

Foreword by Stephen L. Buchwald xiv

Foreword by David Milstein xvi

Preface xvii

1 Key Concepts in Ligand Design: An Introduction 1
Rylan J. Lundgren and Mark Stradiotto

1.1 Introduction 1

1.2 Covalent bond classification and elementary bonding concepts 2

1.3 Reactive versus ancillary ligands 4

1.4 Strong?- and weak?-field ligands 4

1.5 Trans effect 6

1.6 Tolman electronic parameter 6

1.7 Pearson acid base concept 8

1.8 Multidenticity, ligand bite angle, and hemilability 8

1.9 Quantifying ligand steric properties 10

1.10 Cooperative and redox non?-innocent ligands 12

1.11 Conclusion 12

References 13

2 Catalyst Structure and CisTrans Selectivity in Ruthenium?-based Olefin Metathesis 15
Brendan L. Quigley and Robert H. Grubbs

2.1 Introduction 15

2.2 Metathesis reactions and mechanism 17

2.3 Catalyst structure and E/Z selectivity 24

2.4 Z?-selective Ru?-based metathesis catalysts 33

2.5 Cyclometallated Z?-selective metathesis catalysts 36

2.6 Conclusions and future outlook 42

References 43

3 Ligands for Iridium?-catalyzed Asymmetric Hydrogenation of Challenging Substrates 46
Marc?-André Müller and Andreas Pfaltz

3.1 Asymmetric hydrogenation 46

3.2 Iridium catalysts based on heterobidentate ligands 49

3.3 Mechanistic studies and derivation of a model for the enantioselective step 57

3.4 Conclusion 63

References 64

4 Spiro Ligands for Asymmetric Catalysis 66
Shou?-Fei Zhu and Qi?-Lin Zhou

4.1 Development of chiral spiro ligands 66

4.2 Asymmetric hydrogenation 73

4.3 Carboncarbon bond?-forming reactions 85

4.4 Carbonheteroatom bond?-forming reactions 91

4.5 Conclusion 98

References 98

5 Application of Sterically Demanding Phosphine Ligands in Palladium?-Catalyzed Cross?-Coupling leading to C(sp2)E Bond Formation (E = NH2 , OH, and F) 104
Mark Stradiotto and Rylan J. Lundgren

5.1 Introduction 104

5.2 Palladium?-catalyzed selective monoarylation of ammonia 108

5.3 Palladium?-catalyzed selective hydroxylation of (hetero)aryl halides 117

5.4 Palladium?-catalyzed nucleophilic fluorination of (hetero)aryl (pseudo)halides 123

5.5 Conclusions and outlook 129

Acknowledgments 130

References 131

6 Pd?-N?-Heterocyclic Carbene Complexes in Cross?-Coupling Applications 134
Jennifer Lyn Farmer, Matthew Pompeo, and Michael G. Organ

6.1 Introduction 134

6.2 N?-heterocyclic carbenes as ligands for catalysis 135

6.3 The relationship between N?-heterocyclic carbene structure and reactivity 136

6.4 Cross?-coupling reactions leading to CC bonds that proceed through transmetalation 140

6.5 KumadaTamaoCorriu 141

6.6 SuzukiMiyaura 148

6.7 Negishi coupling 163

6.8 Conclusion 170

References 171

7 Redox Non?-innocent Ligands: Reactivity and Catalysis 176
Bas de Bruin, Pauline Gualco, and Nanda D. Paul

7.1 Introduction 176

7.2 Strategy I. Redox non?-innocent ligands used to modify the Lewis acidbase properties of the metal 179

7.3 Strategy II. Redox non?-innocent ligands as electron reservoirs 181

7.4 Strategy III. Cooperative ligand?-centered reactivity based on redox active ligands 192

7.5 Strategy IV. Cooperative substrate?-centered radical?-type reactivity based on redox non?-innocent substrates 195

7.6 Conclusion 200

References 201

8 Ligands for Iron?-based Homogeneous Catalysts for the Asymmetric Hydrogenation of Ketones and Imines 205
Demyan E. Prokopchuk, Samantha A. M. Smith, and Robert H. Morris &lt...