ORGN 622 |
| The synthesis of C2-symmetric NHC-catalysts for use in several reactions has been a topic of recent interest in our group. To our knowledge, there are no reported chiral NHC ligands used for asymmetric cyclopropanations, or asymmetric cyclopropanations from stannyldiazoalkanes. Recent research in our group has shown that NHC-catalyzed reaction of stannyldiazo compounds with alkenes gives rise to diastereoenriched cyclopropanes in 50-71% yield and dr up to 95:5 (1). These high selectivities prompted us to explore the idea of a C-2 symmetric Cu(I) NHC-catalyst for possible use in this and other reactions. In addition we want to explore the effects of creating a chiral environment near the metal through enantioenriched aniline precursors. To do this we have used sparteine mediated organolithium chemistry to establish chirality at the ortho position of the alkyl substituted aniline (2). Progress in this investigation will be presented. 1. R. E. Gawley, S. Narayan, R. E. Gawley and S. Narayan Chem. Commun. 2005, 5109-5111. 2. A. Basu, P. Beak, J. Am. Chem Soc. 1996, 118, 1575-1576. J. A. Wilkinson, S. B. Rossington, S. Ducki, J. Leonard, N. Hussain Tetrahedron Asymmetry 2004, 15, 3011-3013.
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Materials, Devices and Switches, Metal-Mediated Reactions, Asymmetric Reactions, Total Synthesis, Biologically-Related Molecules and Processes
7:00 PM-9:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- La Louisiane, Blrm. C, Poster
Division of Organic Chemistry |
