When one considers the overall representation of frontier orbital filling of hexacoordinate (Oh) and tetracoordinate (Td) inorganic and organo metallic complexes, it clearly appears that out of 26 cases covering both high spin and low spin situations, 21 represent paramagnetic species (K. Purcell, J. Kotz, "Inorganic Chemistry", Saunders, 1977, p561). This would suggest that, if there is a part in chemistry to illustrate the reactivity of radical species, this part certainly is inorganic organometallic chemistry. In contrast with these expectations, and whereas the standard Organic Chemistry textbook (J. March ,"Advanced Organic Chemistry", J. Wiley, N. Y. , 1985) has a specific chapter devoted to free radical reactivity, neither the inorganic standard (FA Cotton, G. Wilkinson, "Advanced Inorganic Chemistry", Wiley, 1988), nor the Organometallic one (J. P. Collman, L. S. Hegedus, J. R. Norton, R. G. Finke, "Principles and Applications of Organotransition Metal Chemistry", University Science Books Mill Valley C. A. , 1987) possess such a specific chapter. The balance is partly restored because the two last cited books have a more comprehensive treatment of electron transfer phenomena. These comparisons show unambiguously that the importance of paramagnetic species in chemical reactivity still lacks a consistent treatment transcending the artificial barriers between branches of Chemistry. This book, which brings together experimental facts and concepts originating from organometallic and organic reactivities, is a step in the direction of bridging this gap. The unifying thread which connects the 35 chapters throughout this book is Activation/Selectivity and Catalysis by means of radical chemistry.

Proceedings of the NATO Advanced Research Workshop, St. Maximin, France, October 4-9, 1987

Zusammenfassung
Proceedings of the NATO Advanced Research Workshop, St. Maximin, France, October 4-9, 1987

Inhalt

1. Selectivity and Stereospecificity in Synthetic Applications of Radical Reactions..- 2. Chain Reactions of Organomercury Halides Involving Electron Transfer..- 3. Redox Catalysis and Electron-Transfer Processes in Selective Organic Syntheses..- 4. Paramagnetic Iron Complexes: their Role in the Transformation of Olefins..- 5. Activation of Co-ordinated II-hydrocarbons by One-Electron Transfer..- 6. Reactions of Photoexcited Carbony Compounds with Silanes: Mechanism and Regioselectivity..- 7. Alkane Functionalization by Mercury Photosensitization..- 8. Metal Vapor Reactivity of Copper Toward Substituted Bromo- benzenes. Comparison with the Classical Ullmann Coupling Reaction..- 9. Recent Advances in the Chemistry of Silyl Radicals..- 10. Divalent Lanthanides: a Family of Reducing Agents in Organic Synthesis..- 11. Electron Transfer Activation of Metal Carbonyls..- 12. Oxidatively Induced Substitution Reactions of Transition Metal Organometallic Compounds..- 13. Competitive Reactivities of Paramagnetic Organometallic Intermediates..- 14. Structure and Substitution Reactions of Nineteen-Electron Organometallic Complexes..- 15. Role of Termination Steps on the Efficiency of Electron Transfer Chain Catalysis..- 16. Molecular Orbital Treatment of Activation Induced by Electron Attachment. Application to Electron Transfer Catalysis..- 17. Structural Consequences of Electron-Transfer in Dinuclear Iron PolyAromatic Complexes..- 18. Activation of Thallium-Carbon and Mercury-Carbon Bonds with Electron Donors..- 19. Electrochemistry of New Molybdenocene Dihydrocarbyls..- 20. Electron Transfer Induced Metal Addition and Ligand Exchange in Organometallic Anion Radical Complexes..- 21. Paramagnetic Species in Photoinduced or Photocatalytic Processes Involving some Cobalt, Titanium and Iron Organometallic Complexes..- 22. Monoelectronic Processes in Iron Complexes and Controlled Reactions by Ancillary PR3 Ligands..- 23. Photolytic Generation of Radicals from [?-C5R5Fe+Arene]* Complexes. Implications for Electron Transfer Catalysis and Radical Reactions..- 24. Photoinduced Radical Chain Bromination of Decarbonyldi- manganese..- 25. Chemistry and Reactivity of Metal Cluster Carbonyl Radical Anions..- 26. Electron Spin Resonance Studies of Organotransition Metal Reactive Intermediates..- 27. Importance of Paramagnetic Organometallic Species in Cluster Electrochemistry..- 28. Electron Transfer-Catalysed Substitution Reactions of Metal Cluster Carbonyls..- 29. The Role of Free Radicals in Organometallic Catalysis..- 30. Organometallic and Radical Chemistry of B12 Coenzymes..- 31. Structure and Reactions of Some Organometallic Radicals..- 32. Competition Between Odd- and Even Electron Processes..- 33. Trapping Intermediates in Electron Transfer Reactions of Square Planar Organometallic d8 Species..- 34. Polar versus Electron Transfer Pathway in the Reaction of Alkyl Lithium and Alkyl Grignard Reagents with Mononitroarenes: Factors affecting Product Distribution..- 35. Reaction of Alkyl Halides with Lithium and Magnesium Reagents. Nucleophilic Substitution versus. Single Electron Transfer..- Participants.- Formula Index.- Author Index.