Enantioselective Titanium-catalysed Transformations

by Helene Pellissier

Overview

Chiral titanium complexes are low-cost, low-toxicity and high-efficiency catalysts. Impressive progress on enantioselective titanium-catalysed transformations has been achieved in the past seven years, with exciting new discoveries ranging from basic reactions to novel methodologies. Despite this, the field has not been substantially reviewed since 2008.This book contains up to date research and covers all types of enantioselective transformations using chiral titanium catalysts. It illustrates the economic, health, and environmental benefits of chiral titanium catalysts, showing the types of highly enantioselective reactions that they are able to induce are unlimited.Work presented here is aimed at researchers in organic and catalytic chemistry, and has been carefully curated to encourage future research possibilities.

Product Details

ISBN-13:	9781783268948
Publisher:	Imperial College Press
Publication date:	03/09/2016
Series:	Catalytic Science Series , #14
Pages:	280
Product dimensions:	6.20(w) x 9.20(h) x 0.70(d)

Table of Contents

General Introduction ix

Chapter 1 Enantioselective Titanium-Promoted Alkylation, Arylation, Alkynylation, Allylation, and Vinylation Reactions of Carbonyl Compounds 1

1.1 Introduction 1

1.2 Titanium-Promoted Alkylation and Arylation Reactions of Carbonyl Compounds 3

1.2.1 Additions of Dialkylzinc Reagents to Carbonyl Compounds 4

1.2.1.1 Aldehydes as electrophiles 4

1.2.1.2 Ketones as electrophiles 21

1.2.2 Additions of Organoaluminum Reagents to Carbonyl Compounds 25

1.2.2.1 Aldehydes as electrophiles 25

1.2.2.2 Ketones as electrophiles 29

1.2.3 Additions of Grignard Reagents to Aldehydes 33

1.2.4 Additions of Organotitanium Reagents to Aldehydes 42

1.2.5 Additions of Alkylboron Reagents to Aldehydes 45

1.2.6 Additions of Organolithium Reagents to Aldehydes 48

1.3 Titanium-Promoted Alkynylation Reactions of Carbonyl Compounds 51

1.3.1 Aldehydes as Electrophiles 51

1.3.1.1 Addition of phenylacetylene 52

1.3.1.2 Addition of various terminal alkynes 59

1.3.1.3 Addition of 1,3-diynes and 1,3-enynes 67

1.3.2 Ketones as Electrophiles 68

1.4 Titanium-Promoted Allylation and Vinylation Reactions of Carbonyl Compounds 71

1.4.1 Allylations 71

1.4.2 Vinylations 75

1.5 Conclusions 78

References 79

Chapter 2 Enantioselective Titanium-Catalysed Cyanation Reactions of Carbonyl Compounds and Derivatives 85

2.1 Introduction 85

2.2 Aldehydes as Electrophiles 87

2.2.1 Cyanations of aldehydes with trimethylsilyl cyanide 87

2.2.1.1 Salenligands 87

2.2.1.2 BINOL-derived ligands 99

2.2.1.3 Schiff base ligands 102

2.2.1.4 Other ligands 105

2.2.2 Cyanations of aldehydes with other sources of cyanide 108

2.2.2.1 Salenligands 108

2.2.2.2 Other ligands 112

2.3 Ketones as Electrophiles 118

2.4 Strecker-Type Reactions 122

2.5 Conclusions 126

References 127

Chapter 3 Enantioselective Titanium-Catalysed Thioether Oxidations 133

3.1 Introduction 133

3.2 Alkyl Hydroperoxides as Oxidants 135

3.3 Hydrogen Peroxide as Oxidant 145

3.4 Conclusions 151

References 152

Chapter 4 Enantioselective Titanium-Catalysed Epoxidation Reactions 155

4.1 Introduction 155

4.2 Ep oxidations using Hydrogen Peroxide 156

4.3 Ep oxidations using Alkyl Hydroperoxides 162

4.4 Darzens Reactions 163

4.5 Conclusions 167

References 167

Chapter 5 Enantioselective Titanium-Catalysed Cycloaddition Reactions 169

5.1 Introduction 169

5.2 (Hetero)-Diels-Alder Cycloadditions 170

5.3 1,3-Dipolar Cycloadditions 176

5.4 Cyclopropanations 180

5.5 Conclusions 182

References 183

Chapter 6 Enantioselective Titanium-Catalysed Aldol-Type Reactions 187

Conclusions 196

References 197

Chapter 7 Enantioselective Titanium-Catalysed Reduction Reactions 199

7.1 Introduction 199

7.2 Hydroaminations 200

7.3 Hydrophosphonylations 202

7.4 Miscellaneous Reductions 205

7.5 Conclusions 208

References 208

Chapter 8 Enantioselective Titanium-Catalysed Ring-Opening Reactions of Epoxides and Aziridines 211

8.1 Introduction 211

8.2 Ring-Opening Reactions of Epoxides 211

8.3 Ring-Opening Reactions of Aziridines 218

8.4 Conclusions 221

References 222

Chapter 9 Enantioselective Titanium-Catalysed Domino and Tandem Reactions 223

Conclusions 232

References 233

Chapter 10 Enantioselective Titanium-Catalysed Miscellaneous Reactions 237

10.1 Introduction 237

10.2 Michael-Type Reactions 237

10.3 Friedel-Crafts Reactions 241

10.4 Other Reactions 243

10.5 Conclusions 249

References 249

General Conclusions 251

References 252

Index 255