ORGN 270 |
| N-heterocyclic carbenes (NHCs) have emerged as an important class of ligands for transition metals and are beginning to play a role in transition metal catalysis. Salts A, B and C are enantiomeric pure amino acids that possess N-heterocyclic carbene precursors as their side chains. Using solid-phase peptide synthesis, these amino acids can be used in a modular approach to synthesize different NHC complexes. After the ligands are synthesized the carbene precursor can be converted to the free carbene and coordinated to a catalytically active transition metal. Compounds A, B and C can be made through a short route starting with oxalyl chloride and the appropriate anilines. The key step is palladium-catalyzed coupling reaction between iodioalanine-derived organozinc reagent and aryl iodide. The solid phase synthesis of peptide-based ligands and the formation of transition metal complexes of the ligands will also be discussed.
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Asymmetric Reactions and Syntheses
8:00 AM-12:00 PM, Monday, 14 March 2005 Convention Center -- Room 11A, Oral
Division of Organic Chemistry |
