ORGN 460 |
| The stereoselective synthesis of tetrahydrofurans and pyrrolidines is an important goal due to the prevalence of these moieties in biologically active natural products. We have recently developed new Pd-catalyzed carboamination and carboetherification reactions for the synthesis of tetrahydrofurans and pyrrolidines from gamma-hydroxy or gamma-amino alkenes and aryl bromides. This presentation describes our studies on intramolecular versions of these reactions that provide 2-(1-indanyl)tetrahydrofurans and -pyrrolidines in good yields with diastereoselectivities of up to >20:1. Transformations of substrates bearing nitrogen nucleophiles are stereospecific and stereoselective, providing products of syn addition of carbon and nitrogen across the double bond. Reactions of substrates bearing primary alcohol nucleophiles are also stereospecific and stereoselective. However, the stereochemical outcome of these transformations can be tuned by varying the metal/phosphine ligand combination to selectively afford products of either syn- or anti addition. Preliminary studies on the mechanism of these transformations will also be presented.
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Metal-Mediated Reactions and Syntheses
8:00 AM-12:00 PM, Wednesday, 29 March 2006 Georgia World Congress Center -- C302, Oral
Division of Organic Chemistry |
