Radical reactions in aqueous media

Chapter 1. Free Radical Chemistry and Green Chemistry: The Historical Perspective

1.1. Radicals: Historical and Practical Importance

1.1.1. What Are Free Radicals

1.1.2. Brief History and Development of Free Radical Chemistry and Evolution of Green Chemistry

1.2. Natural Radical Reactions and Applications

1.3. Autoxidation in Biology: a Brief Chemist's Perspective

1.4. Commercial Radical Reactions

References

Chapter 2. Basic Radical Chemistry: General Aspects of Synthesis with Radicals

2.1. Reactions Between Radicals

2.2. Reaction Between Radical and Non-radical

2.3. Reactivity and Selectivity

2.4. Enthalpy: in Brief

2.5. Entropy

2.6. Steric Effects

2.7. Stereoelectronic Effect

2.8. Polarity

2.9. Elementary Reaction Steps Between Radicals and Non-radicals

2.10. Additions

2.11. Orbital Interaction Between a Nucleophilic Radical and an Electron-poor Alkene

2.12. Orbital Interaction Between an Electrophilic Radical and an Electron-rich Alkene

2.13. Substitution (Abstraction) Reactions

2.14. Elimination

2.15. Rearrangement Reactions

2.16. Termination/Electron Transfer

2.17. Conclusion

References

Chapter 3. Why Water as a Solvent? Reasons and Advantages

3.1. Solubility of Organic Compounds in Water

3.2. Organic Cosolvents

3.4. Ionic Derivatisation (pH Control)

3.5. Surfactants

3.6. Hydrophilic Auxiliaries

3.7. Conclusion

References

Chapter 4. Reducing Agents Based on Group 4 and Aqueous Media

4.1. General Introduction

4.2. Mercury Hydrides and Water: Brief General Reaction Considerations

4.3. Application of Organomercury Hydrides in Synthesis

4.3.1. Perspective and Future Directions

4.4. Bu 3 SnH as a Major Player in-Reductions in Organic Solvents: Would Water be a Possible Solvent for the Transformations?

4.5. Radical Initiators: Choosing the Appropriate Radical Initiator for the Aqueous Free Radical Reaction of Choice

4.6. Reaction Rates and Practical Hints

4.7. Tris(trimethylsilyl)silane: Historical Perspective and What Can Be Done 20 Years After its Discovery as a Radical-based Reducing Agent

4.8. (Me 3 Si) 3 SiH Reagent: How, When and Why to Use

4.9. Tris(trimethylsilyl)silane (TMS 3 SiH) as an Efficient Radical Hydrogen Donor, 'on Water'and 'in Water'

4.10. On 'Polarity Reversal Catalysis' and the Benefits for Silicon-based Reducing Agents in Aqueous Media

4.10.1. Reduction of Water-insoluble Compounds

4.11.2. Reduction of Water-soluble Compounds

References

Chapter 5. On the Use of Phosphorus Hydrides as Efficient Hydrogen Donors

5.1. Introduction: Hypophosphorous Acid (H 3 P0 2 ) as a Free Radical Hydrogen Donor in Aqueous Media

5.2. On the Use of P-centred Radicals as Efficient Hydrogen Donors

5.3. Deoxygenation Reactions in Aqueous Media

5.4. Applications in Synthesis

5.5. Deuterium Labelling and Radicals

5.6. Conclusion

References

Chapter 6. Organoboron Compounds as Radical Reducing Agents

6.1. On the Use of Boron in Atom Transfer Processes

6.1.1. Iodine Atom Transfer

6.1.2. Bromine Atom Transfer

6.2. Organoboranes as Chain Transfer Reagents

6.2.1. Triethylborane-mediated Chain Transfer Reaction via Iodine Atom Transfer

6.3. Organoboron Compounds as Radical Reducing Agents as Complexes with Water and Alcohols

6.4. Conclusion and Future Directions

References

Chapter 7. Carbon-Carbon Bond Formation through Radical Addition Chemistry

7.1. General Principles and Considerations

7.2. Metal-free' Radical Addition to C=C Double Bonds in Water or Aqueous Media

7.3. Indium-mediated Radical Reactions in Aqueous Medium

7.4. Zinc-mediated Alkylations of C=N Bonds: Yet Another Tool in the Carbon-Carbon Bond Formation Toolbox

7.5. Stereoselective Radical Addition to C=N Bonds in Aqueous Media: How Does It Fit?

7.6. Diastereoselective Radical Reactions in Acyclic Systems

7.7. Diastereoselective Free Radical Reactions Under Substrate-controlled Conditions

7.8. Stereoselectivity in Free Radical Alkylation of C=N Bonds in Detail

7.9. Enantioselective Radical Addition Reactions to the C=N Bond Utilising Chiral Quaternary Ammonium Salts of Hypophosphorous Acids in Aqueous Media

7.10. Conclusion and Future Directions

References

Chapter 8. Redox Processes and Electron Transfer: Free Radicals Are a Central Player

8.1. Electron Transfer Processes in General

8.2. Formation of Radicals by Oxidation with Transition Metals Salts: Genera Aspects and Considerations

8.2.1. Oxidations Involving Mn(III) in Aqueous, Ionic Liquids and the Solid State

8.2.2. Oxidations Using Fe(III) Salts (Fenton Reaction) in Aqueous Media: Fenton Chemistry is Yet Another Example of a Novel and Efficient Alkyl Radical Trap in Aqueous Medium

8.3. Formatin of Radicals by Reduction with Transition Metals Salts

8.3.1. General Reaction Considerations

8.3.2. Reductions with Ti(III) Salts in Aqueous Media

8.3.3. Reduction with Sm(II) Iodide in Aqueous Media

8.4. Dissolving Metal Reductions and Aqueous Media

8.5. Electron Transfer from Organic Reducing Agents in Aqueous Media

8.6. Conclusion

References

Chapter 9. Chain versus Non-chain Free Radical Processes in Aqueous Media

9.1. The Persistent Radical Effect: General Principles and Considerations

9.2. Living Free Radical Polymerisations in Aqueous Media

9.3. Mimicking Vitamin B12: the Radical Chemistry of Organocobalt Derivatives in Water and Aqueous Media

References

Chapter 10. Future Directions and Practical Considerations

10.1. Generation of Radicals for Probing DNA Structures

10.2. Helpful Hints and Tips: Radical Generation at the Fingertips

10.2.1. CarbonHalogen Bonds

10.2.2. CarbonOxygen Bonds

10.2.3. CarbonSulfur and CarbonSelenium Bonds

10.2.4. CarbonNitrogen Bonds

10.2.5. Carboxylic acids

10.2.6. Ketones

10.2.7. Cyclopropanes

10.2.8. Alkenes

10.2.9. Alkenes and Aromatic Compounds

10.2.10. CarbonHydrogen Bonds

10.2.11. Carbanions

10.2.12. CarbonBoron Bonds

10.2.13. CarbonMercury Bonds

10.2.14. CarbonCobalt Bonds

References

Further Reading

Subject Index