Rh-Catalyzed Intermolecular Cyclopropanation with α-Alkyl-α-diazoesters: Catalyst-Dependent Chemo- and Diastereoselectivity
Patricia Panne, Andrew DeAngelis and Joseph M. Fox*
*Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Email: jmfoxudel.edu
P. Panne, A. DeAngelis, J. M. Fox, Org. Lett., 2008, 10, 2987-2989.
DOI: 10.1021/ol800983y (free Supporting Information)
In a Rh-catalyzed procedure for the cyclopropanation of alkenes with α-alkyl-α-diazoesters, sterically demanding carboxylate ligands serve to avoid β-hydride elimination. The use of triphenylacetate (TPA) as ligand also imparts high diastereoselectivity.
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