Rh-catalyzed intermolecular cyclopropanation with alpha-alkyl-alpha-diazoesters: catalyst-dependent chemo- and diastereoselectivity.
A Rh-catalyzed procedure for the cyclopropanation of alkenes with alpha-alkyl-alpha-diazoesters is described. With dirhodium tetraoctanoate, the predominant pathway is beta-hydride elimination. While a number of sterically demanding carboxylate ligands serve to avoid beta-hydride elimination, it was found that triphenylacetate (TPA) also imparts high diastereoselectivity.
Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Patricia
P
Panne
Andrew
A
DeAngelis
Joseph M
JM
Fox
D000475:Alkenes / Q000737:chemistry*; D001391:Azo Compounds / Q000737:chemistry*; D002384:Catalysis; D004952:Esters; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism
D000475:Alkenes; D001391:Azo Compounds; D004952:Esters; D012238:Rhodium