Phosphorus(III)Ligands in Homogeneous Catalysis E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1129

Veröffentlichungsjahr: 2012

Beschreibung

Over the last 60 years the increasing knowledge of transition metal chemistry has resulted in an enormous advance of homogeneous catalysis as an essential tool in both academic and industrial fields. Remarkably, phosphorus(III) donor ligands have played an important role in several of the acknowledged catalytic reactions. The positive effects of phosphine ligands in transition metal homogeneous catalysis have contributed largely to the evolution of the field into an indispensable tool in organic synthesis and the industrial production of chemicals.

This book aims to address the design and synthesis of a comprehensive compilation of P(III) ligands for homogeneous catalysis. It not only focuses on the well-known traditional ligands that have been explored by catalysis researchers, but also includes promising ligand types that have traditionally been ignored mainly because of their challenging synthesis.

Topics covered include ligand effects in homogeneous catalysis and rational catalyst design, P-stereogenic ligands, calixarenes, supramolecular approaches, solid phase synthesis, biological approaches, and solubility and separation.

Ligand families covered in this book include phosphine, diphosphine, phosphite, diphosphite, phosphoramidite, phosphonite, phosphinite, phosphole, phosphinine, phosphinidenene, phosphaalkenes, phosphaalkynes, P-chiral ligands, and cage ligands.

Each ligand class is accompanied by detailed and reliable synthetic procedures. Often the rate limiting step in the application of ligands in catalysis is the synthesis of the ligands themselves, which can often be very challenging and time consuming. This book will provide helpful advice as to the accessibility of ligands as well as their synthesis, thereby allowing researchers to make a more informed choice.

Phosphorus(III) Ligands in Homogeneous Catalysis: Design and Synthesis is an essential overview of this important class of catalysts for academic and industrial researchers working in catalyst development, organometallic and synthetic chemistry.

Leseprobe

Contents

List of Contributors

Preface

1 Phosphorus Ligand Effects in Homogeneous Catalysis and Rational Catalyst Design

1.1 Introduction

1.2 Properties of phosphorus ligands

1.3 Asymmetric ligands

1.4 Rational ligand design in nickel-catalysed hydrocyanation

1.5 Conclusions

2 Chiral Phosphines and Diphosphines

2.1 Introduction

2.2 Chiral chelating diphosphines with a linking scaffold

2.3 Chiral atropisomeric biaryl diphosphines

2.4 Chiral phosphacyclic diphosphines

2.5 P-stereogenic diphosphine ligands

2.6 Experimental procedures for the syntheses of selected diphosphine ligands

2.7 Concluding remarks

3 Design and Synthesis of Phosphite Ligands for Homogeneous Catalysis

3.1 Introduction

3.2 Synthesis of phosphites

3.3 Highlights of catalytic applications of phosphite ligands

3.4 General synthetic procedures

4 Phosphoramidite Ligands

4.1 Introduction

4.2 Synthesis of phosphoramidites

4.3 Reactivity of the phosphoramidites

4.4 Types of phosphoramidite ligands

4.5 Conclusion

4.6 Synthetic procedures

5 Phosphinite and Phosphonite Ligands

5.1 Introduction

5.2 General methods for synthesis of complexes

5.3 Syntheses and applications of phosphinite ligands

5.4 Synthesis and applications of phosphonite ligands

5.5 Experimental procedures for the syntheses of prototypical phosphinite and phosphonite ligands

5.6 Acknowledgments

Abbreviations

6 Mixed Donor Ligands

6.1 Introduction: general design principles

6.2 Synthesis of bidentate P,X-ligands

6.3 Conclusion

6.4 Experimental procedures

7 Phospholes

7.1 Introduction

7.2 Creation of phospholes for use as ligands

7.3 Postsynthetic functionalisation

7.4 Phosphole coordination chemistry

7.5 Phospholes in catalysis

7.6 Experimental procedures

8 Phosphinine Ligands

8.1 Introduction

8.2 Ligand properties

8.3 Synthesis of Phosphinines

8.4 Coordination chemistry

8.5 Reactivity of transition metal complexes

8.6 Application of phosphinines in homogeneous catalysis

8.7 Experimental procedure for the synthesis of selected phosphinines

9 Highly Strained Organophosphorus Compounds

9.1 Introduction

9.2 Three-membered rings

9.3 Rearrangements

9.4 Homogeneous catalysis

9.5 Conclusions

9.6 Experimental procedures

10 Phosphaalkenes

10.1 Introduction

10.2 Synthesis of phosphaalkenes

10.3 Catalysis with phosphaalkene ligands

10.4 Concluding remarks

10.5 Experimental procedures for representative ligands

10.6 Acknowledgments

11 Phosphaalkynes

11.1 Introduction

11.2 General experimental

11.3 Preparation of PC t Bu

11.4 Adamanylphosphaalkyne, AdC≡P

11.5 Mesitylphosphaalkyne, MesC≡P

11.6 Phospholide anions

11.7 1,3,5-Triphosphabenzene

12 P-chiral Ligands

12.1 Introduction

12.2 Designing P-chiral ligands using alcohols as chiral auxiliaries

12.3 Designing P-chiral ligands using amino alcohols as chiral auxiliaries

12.4 Designing of P-chiral ligands using amines as chiral auxiliaries

12.5 Conclusion

12.6 Experimental procedures

13 Phosphatrioxa-adamantane Ligands

13.1 Introduction

13.2 Synthesis of phosphatrioxa-adamantanes

13.3 Catalysis supported by phosphatrioxa-adamantane ligands

13.4 Experimental procedures for phosphatrioxa-adamantanes ligands

14 Calixarene-based Phosphorus Ligands

14.1 Introduction

14.2 Conformational properties

14.3 Calixarene-based phosphorus ligands

14.4 Applications in homogeneous catalysis

14.5 Experimental procedures

15 Supramolecular Bidentate Phosphorus Ligands

15.1 Introduction: general design principles

15.2 Construction of bidentate phosphorus ligands via self-assembly

15.3 Conclusions

15.4 Experimental procedures

16 Solid-phase Synthesis of Ligands

16.1 Introduction

16.2 Insoluble supports in ligand synthesis

16.3 Soluble polymeric supports

16.4 Supported ligands in catalysis

16.5 Solid-phase synthesis of nonsupported ligands

16.6 Conclusions and outlook

16.7 Experimental procedures

17 Biological Approaches

17.1 Introduction

17.2 Peptide-based phosphine ligands

17.3 Oligonucleotide-based phosphine ligands

17.4 Phosphine-based artificial metalloenzymes

17.5 Conclusions and outlook

17.6 Representative synthetic procedures

17.7 Acknowledgments

18 The Design of Ligand Systems for Immobilisation in Novel Reaction Media

18.1 Introduction

18.2 Aqueous biphasic catalysis

18.3 Fluorous biphasic catalysis

18.4 Ionic liquids as reaction media

18.5 Supercritical fluids as solvents in single and multiphasic reaction systems

18.6 Experimental section

Index

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Library of Congress Cataloging-in-Publication Data

Kamer, Paul C. J. Phosphorus(III) ligands in homogeneous catalysis : design and synthesis / edited by Paul C. J. Kamer & Piet W. N. M. van Leeuwen. p. cm. Includes bibliographical references and index.

ISBN 978-0-470-66627-2 (hardback)

1. Phosphorus compounds. 2. Ligands. 3. Catalysis. I. Leeuwen, P. W. N. M. van (Piet W. N. M.) II. Title. QD181.P1K36 2012 546′.712595–dc23

2012000246

A catalogue record for this book is available from the British Library.HB ISBN: 9780470666272

List of Contributors

Jérôme BayardonInstitut de Chimie MoléculaireUniversité de Bourgogne9 Avenue ASavary-Dijon-21078FranceDuncan CarmichaelLaboratoire “Hétéroéléments et Coordination”Ecole Polytechnique, CNRSRoute de SaclayF-91128 Palaiseau cedexFranceSergio CastillónDepartament de Química Analítica I Química OrgànicaUniversitat Rovira i VirigiliC/ Marcel·lí Domingo s/n43007 TarragonaSpainDavid J. Cole HamiltonEaStCHEM, School of Chemistry, University of St AndrewsPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomEamonn D. ConradDepartment of ChemistryUniversity of British Columbia2036 Main MallVancouver, BC V6T 1Z1CanadaGregory R. DakeDepartment of ChemistryUniversity of British Columbia2036 Main MallVancouver, BC V6T 1Z1CanadaVerónica de la FuenteDepartament de Química Analítica I Química OrgànicaUniversitat Rovira i VirigiliC/ Marcel·lí Domingo s/n43007 TarragonaSpainRené den HeetenHuntsman Holland BVHuntsman PolyurethanesRozenburg Works, Merseyweg 103197 KG RotterdamThe NetherlandsJohannes G. de VriesDSM Resolve and DSM Innovative Synthesis BVA Unit of DSM Pharma Chemicals, PO Box 186160 MD GeleenThe NetherlandsJulien Dugal-TessierDepartment of ChemistryUniversity of British Columbia2036 Main MallVancouver, BC V6T 1Z1CanadaDerek P. GatesDepartment of ChemistryUniversity of British Columbia2036 Main MallVancouver, BC V6T 1Z1CanadaJason A. GillespieEaStCHEM, School of Chemistry, University of St AndrewsPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomCyril GodardDepartament de Química Analítica I Química OrgànicaUniversitat Rovira i VirigiliC/ Marcel·lí Domingo s/n43007 TarragonaSpainAitor GualDepartament de Química Analítica I Química OrgànicaUniversitat Rovira i VirigiliC/ Marcel·lí Domingo s/n43007 TarragonaSpainSylvain JugéInstitut de Chimie MoléculaireUniversité de Bourgogne9 Avenue ASavary-Dijon-21078FrancePaul C. J. KamerEaStCHEM, School of Chemistry, University of St AndrewsPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomWouter LaanEaStCHEM, School of Chemistry, University of St AndrewsPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomLaurent LefortDSM Resolve and DSM Innovative Synthesis BVA Unit of DSM Pharma Chemicals, PO Box 186160 MD GeleenThe NetherlandsWei LiDepartment of Chemistry and Chemical BiologyRutgers, The State University of New Jersey610 Taylor RoadPiscataway, NJ 08854United StatesAngelica MarsonClariant International Ltd.Rothausstrasse 614132 MuttenzSwitzerlandChristian MüllerFreie Universität BerlinInstitute of Chemistry and BiochemistryFabeckstraße 34-3614195 BerlinGermanyAndreas PfaltzDepartment of ChemistryUniversity of BaselSt. Johanns-Ring 19CH-4056 BaselSwitzerlandPaul G. PringleSchool of ChemistryUniversity of BristolBristol BS8 1TSUnited KingdomT. V. (Babu) RajanBabuDepartment of ChemistryThe Ohio State University100 West 18th AvenueColumbus, OH 43210United StatesJoost N. H. Reek

Supramolecular and Homogeneous Catalysisvan ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XH AmsterdamThe NetherlandsChristopher A. RussellSchool of ChemistryUniversity of BristolBristol BS8 1TSUnited KingdomMichiel C. SamuelsEaStCHEM, School of Chemistry, University of St AndrewsPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomJ. Chris SlootwegDepartment of Chemistry and Pharmaceutical SciencesVU University AmsterdamDe Boelelaan 10831081 HV AmsterdamThe NetherlandsMartin B. SmithDepartment of ChemistryUniversity of LoughboroughLoughborough LE11 3TUUnited KingdomBert H. G. SwennenhuisDepartment of ChemistryTexas A&M University at QatarDohaQatarRené TannertDepartment of ChemistryUniversity of BaselSt. Johanns-Ring 19CH-4056 BaselSwitzerlandNell S. TownsendSchool of ChemistryUniversity of BristolBristol BS8 1TSUnited KingdomJarl Ivar van der VlugtSupramolecular and Homogeneous Catalysisvan ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XH AmsterdamThe NetherlandsPiet W. N. M. van LeeuwenInstitute of Chemical Research of Catalonia (ICIQ)Av. Països Catalans 1643007 TarragonaSpainPaul B. WebbSasol Technology UK LtdPurdie Building, North HaughSt Andrews, Fife KY16 9STUnited KingdomXumu ZhangDepartment of Chemistry and Chemical BiologyRutgers, The State University of New Jersey610 Taylor RoadPiscataway, NJ 08854United StatesErik ZuidemaSABIC Technology & InnovationUrmonderbaan 226167 RD GeleenThe Netherlands

Preface

Phosphorus was named “The Devil’s Element” by John Emsley in his book The Shocking History of Phosphorus. Indeed, ignorance and inexperience can lead to severe problems in the handling and application of phosphorus compounds. From a synthetic point of view, the chemistry of phosphorus is challenging and does not always follow the predicted routes. Nevertheless, the synthesis of tervalent phosphorus compounds has been well developed and the rich chemistry of phosphorus not only is crucial in biological systems but also has led to numerous useful applications and materials. Tervalent phosphorus compounds have proven to be extremely powerful in the field of homogeneous catalysis, both in academic research and in industrial applications.

This book covers the important area of the design and synthesis of P(III) donor ligands in homogeneous catalysis. The reactivity of organotransition metal complexes is dependent on the ligand environment of the metal. Consequently, optimizing the catalytic center by varying the ligand properties is a powerful tool in homogeneous catalysis. Impressive results have been obtained in both small-scale (asymmetric) catalytic preparation of fine chemicals and industrial production of bulk chemicals. In the introductory Chapter 1, common methods for using quantitative ligand parameters are discussed, illustrating how rational ligand design can be achieved.

Even so, while increasing knowledge about organotransition–metal compounds and computational ­chemistry has provided fundamental knowledge of the factors influencing elementary reaction steps, catalyst development is often hampered by synthesis of ligands with the appropriate structure. This is probably the reason that the majority of catalytic studies are still being performed employing traditional phosphine and phosphite ligands, with the exception of sophisticated bidentate ligands such as those employed in ­asym­metric catalysis. Moreover, these ligands are very often relatively simple structures; over the last decades, the most commonly used ligands for homogeneous catalysis are based on triphenylphosphine derivatives. To develop new catalysts for as yet uncatalyzed reactions, existing catalysts must undergo major improvements. Discovery of new catalytic transformations requires the exploration of new transition metal complexes with very diverse and totally new ligand systems. In this book we aim to address the design and synthesis of a comprehensive compilation of P(III) ligands for homogeneous catalysis. We will not only focus on the well-known traditional ligands that have been explored by catalysis researchers, but also include promising ligand types that have traditionally been ignored mainly because of their challenging synthesis. To promote the application of phosphine ligands in catalysis and to increase the practical value of the book, we have included detailed and reliable synthetic procedures in the book, provided by leading experts in the field. This may be of particular importance for the less traditional phosphine ligands, and their synthesis should no longer form a barrier for their use. In our opinion, this renders the book an invaluable reference book for researchers in the fields of catalysis and organic synthesis.

Naturally, the first chapters will cover the syntheses and applications of traditional tervalent phosphorus donor ligands that have successfully been applied in homogeneous catalysis. Triarylphosphine ligands have been widely investigated after the seminal discovery of Wilkinson that rhodium phosphine complexes are excellent hydrogenation catalysts. This has triggered a tremendous boost in synthetic and catalytic studies of phosphine ligands, which is reviewed in Chapter 2. Soon after the first applications of phosphines, catalytic studies based on related ligand structures have been reported, such as phosphites (Chapter 3), ­phosphoramidites (Chapter 4), and phosphonites and phosphinites (Chapter 5).

In organometallic chemistry, phosphorus donor ligands are known for their large trans labilizing effects. By combining phosphorus donors with other donor atoms, resulting in mixed-donor ligand systems, the different trans effects can be exploited to steer regioselectivity of catalytic transformations, which is described in Chapter 6.

Parallel to developments in the synthesis of traditional phosphorus donor ligands, there has been great progress in the field of phosphorus chemistry leading to a plethora of new compounds which have not been intensively studied as ligands in homogeneous catalysis, but do have potential.

Promising examples are P-containing heterocycles such as phospholes (Chapter 7) and phosphinines (Chapter 8). Other relatively unexploited ligand systems are highly strained phosphorus compounds (Chapter 9), low-valent phosphorus donors such as phosphaalkenes (Chapter 10), or even phosphaalkynes (Chapter 11). In ­contrast to its congener nitrogen, the barrier for a Walden inversion of phosphorus is high, allowing for the synthesis of P-stereogenic phosphorus ligands (Chapter 13) and bringing the chiral center in close ­proximity to the metal. Extremely bulky cage compounds (Chapter 12) and well-organized hemispherical calixarene-based ligands (Chapter 14) can lead to surprising steric effects and shape selectivity, ­respectively. Many of these phosphorus compounds have been regarded as chemical curiosities in the past and their investigations have mainly been addressed from a synthetical and theoretical point of view. These ­phosphorus compounds possess defined electronic, steric, and coordination properties that differ from those of the ­classical triphenylphosphine derivatives and can be tuned for optimal selectivity of important catalytic ­reaction steps. In general a catalytic transformation consists of several elementary steps that will be ­influenced in different ways by ligand modifications. These relatively scarcely explored compounds might provide many (pleasant or unpleasant) surprises in catalysis research.

Several approaches can be anticipated to facilitate the synthesis of libraries of phosphorus donor ligands; examples are the supramolecular assembly of bidentate ligands (Chapter 15) or the solid-phase synthesis of immobilized catalyst systems (Chapter 16).

The oxygen sensitivity of most tervalent phosphorus compounds renders them unsuitable as cofactors in biological systems. Therefore, the use of powerful phosphorus donor ligands in protein-based catalysts is restricted to the realm of artificial metalloenzymes (Chapter 17).

Finally, as most phosphorus donor ligand systems are being applied in homogeneous catalysis, ample research has been dedicated to the important problem of catalyst separation and recycling. The present state-of-the-art methods are reviewed in Chapter 18.

The recognition of the catalytic power of phosphorus donor ligands in catalysis is beyond doubt, but in spite of this, relatively few classes have been thoroughly investigated. We believe that the synthetic ­difficulties of the less conventional phosphorus ligands are most likely the reason for this. In this book, we want to ­discuss the chemistry of both well-established and unconventional ligand classes and make them accessible to catalysis researchers by including experimental procedures for representative examples of each ligand class provided by renowned experts in the field. The presentation of the established ligands will certainly lead to new ideas as regards new structures as well as new applications.

1

Phosphorus Ligand Effects in Homogeneous Catalysis and Rational Catalyst Design

Jason A. Gillespie1, Erik Zuidema2, Piet W. N. M. van Leeuwen3, and Paul C. J. Kamer1

1 EaStCHEM, School of Chemistry, University of St Andrews, St Andrews, United Kingdom2 SABIC Technology & Innovation, Geleen, The Netherlands3 Institute of Chemical Research of Catalonia (ICIQ), Tarragona, Spain

1.1 Introduction

Over the last 60 years, the increasing knowledge of transition metal chemistry has resulted in an enormous advance of homogeneous catalysis as an essential tool in both academic and industrial fields. The ­continuously growing importance of transition metal catalysis is well illustrated by the recent awards of three Nobel Prizes in 2001, 2005 and 2010 to this field of chemistry. Remarkably, phosphorus(III) donor ligands have played an important role in several of the acknowledged catalytic reactions [1–5]. The positive effects of ­phosphine ligands in transition metal homogeneous catalysis have contributed largely to the evolvement of the field into an indispensable tool in organic synthesis and the industrial production of chemicals.

An astounding diversity of ligand types and structures is known in literature: mono-, bi- and polydentates, ligands based on single donoratoms (such as phosphorus or nitrogen) or multiple donoratoms (such as P–N or P–O), achiral or chiral ligands, and ligands with exotic steric or electronic constraints. This extensive ligand library is in part the result of the fast developments in organometallic chemistry leading to a wide variety of ligand structures which have been exploited in transition metal complexes. Furthermore, the urge to optimise transition metal complex properties such as catalytic performance triggered an evolutionary type of growth of ligand libraries. Systematic variation and combination of successful ligand structures, intended to optimise ligand performance, inevitably led to new and unprecedented properties, in addition to the expected optimised catalytic systems.

Figure 1.1 represents an extremely tiny sampling of phosphorus donor ligands successful in diverse ­catalytic reactions, displaying an incredibly large variety in their structure. A striking feature is that ligands of very different structures can provide similarly high efficiency in the same catalytic reaction while ligands with very similar structures can behave very differently. The first row in Figure 1.1 shows successful ligands in asymmetric hydrogenation. The monodentate ligand R-camp provided good enantioselectivity in the asymmetric hydrogenation of dehydro amino acids [6], but Knowles et al. showed that bidentate ligands like dipamp performed superior compared to monodentates [7]. Unexpectedly, Feringa and de Vries showed two decades later that monodentates like S-monophos can outperform bidentate ligands [8]. The ligands on the second row are structurally quite different and showed different coordination modes in hydridorhodium ­carbonyl complexes; R,R-chiraphite coordinates in bisequatorial fashion in the trigonal bipyramidal rhodium complex [9], whereas binaphos occupies an apical and an equatorial site [10]. Nevertheless, both ligands perform well in asymmetric hydroformylation of styrene. All three ligands of the third row perform well in palladium-catalyzed asymmetric allylic substitution, although the ligands are based on different types of chirality and/or donor atom type [11–13]. Finally, ligands such as BINAP (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) show excellent performance in several catalytic reactions [1], which instigated Jacobsen to coin such ligands ‘privileged’ ligands [14].

Figure 1.1Selection of phosphorus(III) ligands.

When designing a new catalyst, the choice of the metal is naturally of utmost importance. This choice is usually dictated by the envisaged catalytic reaction and based on pre-existing knowledge or by screening via trial and error. Although most transition metals are capable of facilitating all elementary steps which ­constitute a catalytic cycle, several catalytic reactions are dominated by specific metals such as palladium for allylic substitutions and rhodium for the hydroformylation of alkenes. The next step is, in general, adjusting the reactivity of the metal by adding donor ligands. It is not surprising that the nature of the donor atom is pivotal in influencing the reactivity of the metal. The σ-donor and π-acceptor properties as well as the steric congestion imposed on the metal strongly influence the catalyst performance. In the case of bidentate ligands, the bite angle enforced on the metal also has a profound effect on the steric and electronic properties of the metal (Figure 1.2). Ligand effects are very powerful, and in fact different combinations of transition metals and donor ligands can result in very similar reactivity. Figure 1.2 shows which points of variation may be ­considered when designing new bidentate catalysts.

Figure 1.2Schematic representation of parameters used to design new and optimize existing catalysts.

Phosphorus has often been the donor atom of choice, and it has a long history as a soft, strongly ligating atom for late-transition metals, which is easily rationalised by hard/soft acid base theory. Moreover, in-depth ­understanding of the effects of phosphorus ligands on the properties of transition metal complexes is greatly advanced by facile analysis by P NMR spectroscopy; in fact, the many successes of phosphorus ligands in the field of homogeneous catalysis might very well be mainly due to this easy structural (in situ) analysis by NMR.