Wiley.com
Print this page Share
E-book

N-Heterocyclic Carbenes: Effective Tools for Organometallic Synthesis

Steven P. Nolan (Editor)
ISBN: 978-3-527-67124-3
568 pages
July 2014
N-Heterocyclic Carbenes: Effective Tools for Organometallic Synthesis (3527671242) cover image

Description

This comprehensive reference and handbook covers in depth all major aspects of the use of N-heterocyclic carbene-complexes in organic synthesis: from the theoretical background to characterization, and from cross-coupling reactions to olefin metathesis.
Edited by a leader and experienced scientist in the field of homogeneous catalysis and use of NHCs, this is an essential tool for every academic and industrial synthetic chemist.
See More

Table of Contents

List of Contributors XVII

Preface XXI

1 N-Heterocyclic Carbenes 1
David J. Nelson and Steven P. Nolan

1.1 Introduction 1

1.2 Structure and Properties of NHCs 1

1.3 Abnormal Carbenes 5

1.4 Why Are NHCs Stable? 6

1.5 Bonding of NHCs to Metal Centers 8

1.6 Quantifying the Properties of NHCs 13

1.6.1 Steric Impact 13

1.6.2 Electronic Properties 14

1.7 N-Heterocyclic Carbenes in the Context of Other Stable Carbenes 16

1.8 Synthesis of NHCs 19

1.9 Salts and Adducts of NHCs 20

1.10 Summary 22

References 22

2 Tuning and Quantifying Steric and Electronic Effects of N-Heterocyclic Carbenes 25
Laura Falivene, Albert Poater, and Luigi Cavallo

2.1 Introduction 25

2.2 Steric Effects in NHC ligands 26

2.3 Electronic Effects in NHC Ligands 31

2.4 Conclusions 35

References 35

3 Chiral Monodendate N-Heterocyclic Carbene Ligands in Asymmetric Catalysis 39
Linglin Wu, Alvaro Salvador, and Reto Dorta

3.1 Introduction 39

3.2 NHC–Ru 40

3.2.1 Asymmetric Metathesis 40

3.2.2 Asymmetric Hydrogenation 44

3.2.3 Asymmetric Hydrosilylation 47

3.3 NHC–Rh 48

3.3.1 Asymmetric Catalysis Using Boronic Acids as Nucleophiles 48

3.3.2 Asymmetric Hydrosilylation 50

3.3.3 Asymmetric Hydroformylation 53

3.4 NHC–Ir 53

3.5 NHC–Ni 55

3.6 NHC–Pd 56

3.6.1 Asymmetric Intramolecular α-Arylation of Amides 56

3.6.2 Asymmetric Diamination 62

3.6.3 Other Asymmetric Catalysis Using NHC–Pd 63

3.7 NHC–Cu 65

3.7.1 Asymmetric Conjugate Addition 65

3.7.2 Asymmetric Allylic Substitution 67

3.7.3 Silyl Conjugate Addition 69

3.7.4 Enantioselective β-Boration 70

3.7.5 Asymmetric Hydrosilylation 72

3.7.6 Asymmetric Addition to Imines 73

3.8 NHC–Ag 75

3.9 NHC–Au 75

3.9.1 Enantioselective Cycloisomerizations 76

3.9.2 Enantioselective Hydrogenation 78

3.9.3 Enantioselective Cycloaddition 79

3.10 Conclusion 79

References 80

4 (N-Heterocyclic Carbene)–Palladium Complexes in Catalysis 85
Mario Hoyos, Daniel Guest, and Oscar Navarro

4.1 Introduction 85

4.2 Cross-Coupling Reactions 85

4.2.1 Suzuki–Miyaura Coupling 85

4.2.2 Buchwald–Hartwig Aminations 88

4.2.3 Negishi Reactions 89

4.2.4 Hiyama Coupling 89

4.2.5 Kumada Coupling 90

4.2.6 Sonogashira Coupling 90

4.2.7 Heck Reaction 92

4.3 Chelates and Pincer Ligands 93

4.4 Asymmetric Catalysis 97

4.5 Oxidation Reactions 100

4.6 Telomerization, Oligomerization and Polymerization 102

4.7 Anticancer NHC–Pd Complexes 107

References 107

5 NHC Platinum(0) Complexes: Unique Catalysts for the Hydrosilylation of Alkenes and Alkynes 111
Steve Dierick and István E. Markó

5.1 Introduction 111

5.2 Hydrosilylation of Alkenes: The Beginning 112

5.3 Initial Results with Phosphine Ligands 114

5.4 NHC Platinum(0) Complexes: The Breakthrough 115

5.4.1 Synthesis of NHC Platinum(0) Complexes and Kinetic Assays 115

5.4.2 Functional Group Tolerance and Substrate Scope 120

5.4.3 Mechanistic Studies 122

5.5 Hydrosilylation of Alkynes 133

5.5.1 Catalyst Screening and the Impact of NHCs on Regioselectivity 134

5.5.2 Influence of Silane on Regioselectivity 137

5.5.3 Second-Generation Catalyst for the Hydrosilylation of Alkynes 138

5.5.4 Functional Group Tolerance and Substrate Scope 139

5.5.5 Mechanistic Studies 142

5.6 Conclusions 146

References 146

6 Synthesis and Medicinal Properties of Silver–NHC Complexes and Imidazolium Salts 151
Patrick O. Wagers, Kerri L. Shelton, Matthew J. Panzner, Claire A. Tessier, and Wiley J. Youngs

6.1 Introduction 151

6.2 Silver–NHC Complexes as Antimicrobial Agents 152

6.3 Silver–NHC Complexes as Anticancer Agents 163

6.4 Conclusions 170

References 171

7 Medical Applications of NHC–Gold and –Copper Complexes 173
Faïma Lazreg and Catherine S. J. Cazin

7.1 Introduction 173

7.2 Gold Antimicrobial Agents 173

7.3 Metals as Antitumor Reagents 178

7.4 Copper Complexes as Antitumoral Reagents 195

7.5 Conclusion 196

References 197

8 NHC–Copper Complexes and their Applications 199
Faïma Lazreg and Catherine S. J. Cazin

8.1 Introduction 199

8.2 History of NHC–Copper Systems 199

8.3 Hydrosilylation 200

8.4 Allene Formation 202

8.5 1,4-Reduction 205

8.6 Conjugate Addition 206

8.6.1 Zinc Reagents 206

8.6.2 Grignard Reagents 207

8.6.3 Aluminum Reagents 209

8.6.4 Boron Reagents 209

8.7 Hydrothiolation, Hydroalkoxylation, Hydroamination 210

8.8 Carboxylation and Carbonylation (via Boronic Acids, CH Activation): CO2 Insertion 213

8.9 [3 + 2] Cycloaddition Reaction: Formation of Triazole 215

8.10 Allylic Substitution 217

8.10.1 Zinc Reagents 217

8.10.2 Grignard Reagents 217

8.10.3 Aluminum Reagents 219

8.10.4 Boron Reagents 220

8.11 Carbene and Nitrene Transfer 221

8.12 Boration Reaction 222

8.12.1 Boration of Ketone and Aldehyde 222

8.12.2 Boration of Alkene 223

8.12.3 Boration of Alkyne 224

8.12.4 Carboboration 226

8.13 Olefination of Carbonyl Derivatives 226

8.14 Copper-Mediated Cross-Coupling Reaction 228

8.15 Fluoride Chemistry 230

8.16 Other Reactions 231

8.16.1 A3 Coupling 231

8.16.2 Semihydrogenation of Alkyne 232

8.16.3 Borocarboxylation of Alkyne 233

8.16.4 Hydrocarboxylation of Alkyne 234

8.17 Transmetalation 235

8.18 Conclusion 237

References 237

9 NHC–Au(I) Complexes: Synthesis, Activation, and Application 243
Thomas Wurm, Abdullah Mohamed Asiri, and A. Stephen K. Hashmi

9.1 Introduction 243

9.2 Synthesis of NHC–Gold(I) Chlorides 244

9.3 Activation of NHC–Au(I) Chlorides 248

9.4 Applications of NHC–Au(I) Catalysts 253

9.4.1 Improvement of Catalyst Stability During Gold-Catalyzed Reactions Due to the Use of NHC Ligands 253

9.4.2 Improvement of Gold Catalysis Due to Tuning the Steric Properties of the NHC Ligands Used 256

9.4.3 Improvement of Gold Catalysis by Tuning the Electronic Properties of the NHC Ligands Used 257

9.4.4 Alteration of the Reactivity of Gold Catalysis by Switching from Phosphine to NHC Ligands 258

9.4.5 Enantioselective Gold Catalyzed Transformations Based on Chiral, Enantiopure NHC-Based Catalysts 264

9.5 Conclusion 266

References 267

10 Recent Developments in the Synthesis and Applications of Rhodium and Iridium Complexes Bearing N-Heterocyclic Carbene Ligands 271
Macarena Poyatos, Gregorio Guisado-Barrios, and Eduardo Peris

10.1 Introduction 271

10.2 Rh– and Ir–NHC-Based Complexes: Structural and Electronic Features 271

10.2.1 Mono-NHCs 271

10.2.2 Chelating NHCs 273

10.2.3 Bridging NHCs 282

10.3 Catalytic Applications of Rhodium and Iridium NHC-Based Complexes 288

10.3.1 Reductions 288

10.3.2 Arylation and Borylation Reactions with Organoboron Reagents 293

10.3.3 Oxidations 295

10.3.4 Other Important Catalytic Processes 296

10.4 Abbreviations 298

References 299

11 N-Heterocyclic Carbene–Ruthenium Complexes: A Prominent Breakthrough in Metathesis Reactions 307
Sudheendran Mavila and N. Gabriel Lemcoff

11.1 Introduction 307

11.2 Variations of NHC in Ruthenium Complexes 313

11.3 Modifications in Imidazol- and Imidazolin-2-ylidene Ligands 313

11.4 Influence of Symmetrically 1,3-Substituted N-Heterocyclic Carbene in Metathesis 313

11.4.1 N, N´-Dialkyl Substituted N-Heterocyclic Carbene Complexes 313

11.4.2 N, N´-Diaryl Substituted N-Heterocyclic Carbene Complexes 314

11.5 Unsymmetrically N,N´-Substituted N-Heterocyclic Carbenes 319

11.5.1 N-Alkyl-N´-Aryl Substituted N-Heterocyclic Carbene Complexes 319

11.5.2 N, N´-Diaryl-Substituted N-Heterocyclic Carbene Complexes 323

11.5.3 Influence of 4,5-Substituted N-Heterocyclic Carbenes in Metathesis 325

11.5.4 Four-, Six-, and Seven-Membered N-Heterocyclic Carbenes 327

11.5.5 Heteroatom Containing N-Heterocyclic Carbenes 328

11.5.6 N-Heterocyclic Carbene Bearing Chiral Ru Complexes 330

11.5.7 Chiral Monodentate N-Heterocyclic Carbenes 330

11.5.8 Chiral Bidentate N-Heterocyclic Carbenes 334

11.5.9 NHCs for Metathesis in Water and Protic Solvents 335

References 337

12 Ruthenium N-Heterocyclic Carbene Complexes for the Catalysis of Nonmetathesis Organic Transformations 341
Leonid Schwartsburd and Michael K. Whittlesey

12.1 Introduction 341

12.2 Transfer Hydrogenation 341

12.3 Direct Hydrogenation (and Hydrosilylation) 346

12.4 Borrowing Hydrogen 351

12.5 Alcohol Racemization 356

12.6 Arylation 357

12.7 Reactions of Alkynes 359

12.8 Isomerization of C.C Bonds 360

12.9 Allylic Substitution Reactions 361

12.10 Miscellaneous Reactions 363

12.11 Conclusions 365

References 365

13 Nickel Complexes of N-Heterocyclic Carbenes 371
M. Taylor Haynes II, Evan P. Jackson, and John Montgomery

13.1 Introduction 371

13.2 Nickel–NHC Catalysts 372

13.2.1 In Situ Methods to Generate Ni–NHC Complexes 372

13.2.2 Discrete Ni(0)–NHC Catalysts 373

13.2.3 Discrete Ni(I)–NHC Catalysts 374

13.2.4 Discrete Ni(II)–NHC Catalysts 374

13.3 Cross-Coupling Reactions 376

13.3.1 Carbon–Carbon Bond Forming Reactions 376

13.3.2 Carbon–Heteroatom Bond-Forming Reactions 382

13.4 Oxidation/Reduction Reactions 383

13.4.1 Dehalogenation 383

13.4.2 Imine Reduction 383

13.4.3 Alcohol Oxidation 384

13.4.4 Aryl Ether Reduction 384

13.5 Hydrosilylation 385

13.5.1 Hydrosilylation of Alkynes 385

13.5.2 Hydrosilylation of Carbonyls 385

13.6 Cycloadditions 386

13.6.1 [2+2+2] Cycloaddition 386

13.6.2 [3+2] Cycloaddition 388

13.6.3 [4+2+2] Cycloaddition 389

13.7 Isomerization 390

13.8 Reductive Coupling 390

13.8.1 Aldehydes and Dienes 390

13.8.2 Aldehydes and Alkynes 391

13.8.3 Aldehydes and Allenes 392

13.8.4 Aldehydes and Norbornene 393

13.9 Conclusions and Outlook 393

References 394

14 Coordination Chemistry, Reactivity, and Applications of Early Transition Metal Complexes Bearing N-Heterocyclic Carbene Ligands 397
Stéphane Bellemin-Laponnaz and Samuel Dagorne

14.1 Introduction 397

14.2 Group 3 Metal Complexes 398

14.3 Group 4 Metal Complexes 402

14.4 Group 5 Metal Complexes 411

14.5 Group 6 Metal Complexes 413

14.6 Group 7 Metal Complexes 418

14.7 Conclusion 421

References 422

15 NHC Complexes of Main Group Elements: Novel Structures, Reactivity, and Catalytic Behavior 427
Luke J. Murphy, Katherine N. Robertson, Jason D. Masuda, and Jason A. C. Clyburne

15.1 Introduction 427

15.2 Structures of Common NHCs for Main Group Chemistry 428

15.3 NHC Complexes of Group 1 Elements 429

15.3.1 Lithium 429

15.3.2 Sodium 432

15.3.3 Potassium 433

15.4 NHC Complexes of Group 2 Elements 434

15.4.1 Beryllium 434

15.4.2 Magnesium 436

15.4.3 Calcium, Strontium, and Barium 437

15.5 NHC Complexes of Group 13 Elements 438

15.5.1 Boron 438

15.5.2 Aluminum 452

15.5.3 Gallium 454

15.5.4 Indium and Thallium 456

15.6 NHC Complexes of Group 14 Elements 456

15.6.1 Carbon 456

15.6.2 Silicon 459

15.6.3 Germanium 464

15.6.4 Tin and Lead 466

15.7 NHC Complexes of Group 15 Elements 467

15.7.1 Nitrogen 467

15.7.2 Phosphorus 468

15.7.3 Arsenic and Antimony 473

15.8 NHC Complexes of Group 16 Elements 474

15.8.1 Oxygen and Sulfur 474

15.8.2 Selenium 474

15.8.3 Tellurium 475

15.9 NHC Complexes of Group 17 Elements 476

15.10 NHC Reactivity with Protic Reagents 477

15.11 Cyclic Alkyl Amino Carbenes: Closely Related Cyclic Cousins to NHCs with Similar and Differing Reactivities 478

15.11.1 Boron 479

15.11.2 Carbon 481

15.11.3 Silicon 482

15.11.4 Nitrogen 483

15.11.5 Phosphorus 483

15.12 Summary and Outlook 487

References 488

16 Catalysis with Acyclic Aminocarbene Ligands: Alternatives to NHCs with Distinct Steric and Electronic Properties 499
LeGrande M. Slaughter

16.1 Introduction 499

16.2 Metalation Routes of Acyclic Carbene Ligands 500

16.3 Ligand Properties of Acyclic Carbenes 502

16.3.1 Donor Ability 502

16.3.2 Structural Properties 503

16.3.3 Decomposition Routes 504

16.4 Catalytic Applications 505

16.4.1 Coupling Reactions 505

16.4.2 Allylic Alkylations 509

16.4.3 Olefin Metathesis 510

16.4.4 Gold Catalysis 510

16.4.5 Enantioselective Catalysis with Chiral Acyclic Carbenes 513

16.5 Frontiers in Acyclic Carbene Chemistry 516

16.6 Conclusion 521

References 521

Index 525

See More

Author Information

Steven P. Nolan was born in Canada. He received his B.Sc. in Chemistry from the University of West Florida and his Ph.D. from the University of Miami where he worked under the supervision of Professor Carl D. Hoff. After a postdoctoral stay with Professor Tobin J. Marks at Northwestern University, he joined the Department of Chemistry of the University of New Orleans in 1990. In 2006 he joined the Institute of Chemical Research of Catalonia (ICIQ) as Group leader and ICREA Research Professor. In early 2009, he joined the School of Chemistry at the University of St Andrews where he is Professor and holds the Chair in Inorganic chemistry.






See More

Related Titles

Back to Top