ORGN 266 |
| The conjugate addition of organometallic reagents to enones and related substrates comprises one of the key C-C bond forming transformations in synthetic chemistry. The development of highly enantioselective catalytic versions of these reactions has been a major challenge over the past decades. In this lecture the first highly enantioselective catalytic system for the conjugate addition of Grignard additions to enones is presented. Copper-catalysts based on Taniaphos and Josiphos ligands show high activity and unprecedented levels of enantioselectivity. A study of several parameters including ligand, solvent, counterions, nature of organometallic reagents and preliminary mechanistic studies will be presented. Methodology for the conjugate addition to cyclic and acyclic enones and esters will be presented as well as recent progress regarding scope and limitations of this transformation. |
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Metal-Mediated Reactions and Syntheses
1:00 PM-5:00 PM, Monday, 29 August 2005 Washington DC Convention Center -- 202B, Oral
Division of Organic Chemistry |