In Pursuit of an Ideal Carbon-Carbon Bond-Forming Reaction: Development and Applications of the Hydrovinylation of Olefins

Abstract

Attempts to introduce the highly versatile vinyl group into other organic molecules in a chemo-, regio-, and stereoselective fashion via catalytic activation of ethylene provided challenging opportunities to explore new ligand and salt effects in homogeneous catalysis. This review provides a personal account of the development of enantioselective reactions involving ethylene.

1 Introduction

1.1 The Origins

1.2 Olefin Dimerization Reactions

2 Hydrovinylation Reactions

2.1 A Brief History of Hydrovinylation Reactions

2.2 Ruthenium- and Cobalt-Catalyzed Hydrovinylation Reactions

2.3 Best Practices prior to 1997: Nickel-Catalyzed Hydrovinyl-ation Reactions

2.4 Mechanism of the Nickel-Catalyzed Hydrovinylation of ­Vinylarenes

2.5 A New Protocol for Hydrovinylation Amenable to Asymmetric Catalysis

2.6 Heterodimerization of Vinylarenes with Other Olefins

2.7 Other Heterodimerization Reactions

2.8 Hydrovinylation of Norbornene

3 Enantioselective Hydrovinylation Reactions

3.1 Azaphospholene Ligands

3.2 Aminophosphine/Phosphinite Ligands

3.3 Use of Chelating Phosphines

4 Synergistic Relation between Hemilabile Ligands and Counterions

4.1 New Ligands for Asymmetric Hydrovinylation Reactions: 2-Alkoxy-2′-diphenylphosphino-1,1′-binaphthyl Derivatives

4.2 Effect of Hemilabile Groups

4.3 Solvent and Salt Effects

4.4 Electronic Effects

4.5 Other Protocols for Nickel-Catalyzed Hydrovinylation ­Reactions

4.6 A Model for Asymmetric Induction in Hydrovinylation ­Reactions

4.7 De Novo Design of an Asymmetric Ligand: Hemilabile Phospholanes

4.8 Diarylphosphinite Ligands

4.9 Phosphite Ligands

4.10 Phosphoramidite Ligands

5 Generation of All-Carbon Quaternary Centers

6 Asymmetric Hydrovinylation of 1,3-Dienes

7 Asymmetric Hydrovinylation of Norbornene

8 Applications of Asymmetric Hydrovinylation Reactions

8.1 (S)-2-Arylpropionic Acids

8.2 (R)-α-Curcumene and (R)-ar-Turmerone

8.3 Control of the Configuration of the Steroidal D-Ring Side Chain

8.4 Intramolecular Reactions: Synthesis of Carbocyclic and Heterocyclic Compounds

9 Large-Scale Synthesis

10 Summary and Future Prospects

Key words

carbon-carbon bond formation - hydrovinylations - asymmetric catalysis - ligand effects - transition metals

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  Dan Mans in our group has since completed the synthesis of a number of pseudopterosin aglycones by applying back-to-back enantioselective hydrovinylations of vinylarenes and dienes. This work will be reported in due course.

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34

For a structurally related, unreactive neutral Pd complex, see ref. 12b.

42

For a report on the use of a phosphinite ligand in a Pd-catalyzed hydrovinylation, see ref. 13.

48

To the best of our knowledge, ligand 87 has not been described in the literature. For a complete list of the phosphoramidites used in this study and its corresponding supporting information, see ref. 47.

49

Only naproxen is currently sold in an enantiomerically pure form. For a review of the practical aspects of the synthesis of 2-arylpropionic acids, see ref. 5a.

63

For an extensive list of related references, see ref. 56.

65

For reviews of the synthesis of 2-arylpropionic acids, see ref. 5.

67

Smith, C. R.; RajanBabu, T. V. J. Org. Chem. 2009, 74, in press.

69

For a comparison of the various methods for the synthesis of curcumene, see ref. 71.