Asymmetric Addition of Alkylzinc Reagents to Cyclic α,β-Unsaturated Ketones and a Tandem Enantioselective Addition/Diastereoselective Epoxidation with Dioxygen
Sang-Jin Jeon and Patrick J. Walsh*
*P. Roy and Diane T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, Email: pwalshsas.upenn.edu
S.-J. Jeon, P. J. Walsh, J. Am. Chem. Soc., 2003, 125, 9544-9545.
An asymmetric 1,2-addition of alkyl groups to conjugated cyclic enones gave allylic alcohols with chiral quaternary centers. The resultant allylic alcohols are converted into epoxy alcohols with excellent diastereoselectivities. A semipinacol rearrangement provided α,α-dialkyl-β-hydroxy ketones with all-carbon chiral quaternary centers.
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A Green Chemistry Approach to a More Efficient Asymmetric Catalyst: Solvent-Free and Highly Concentrated Alkyl Additions to Ketones
S.-J. Jeon, H. Li, P. J. Walsh, J. Am. Chem. Soc., 2005, 127, 16416-16425.
Highly Enantio- and Diastereoselective One-Pot Synthesis of Acyclic Epoxy Alcohols with Three Contiguous Stereocenters
A. E. Lurain, A. Maestri, A. R. Kelli, P. J. Carroll, P. J. Walsh, J. Am. Chem. Soc., 2004, 126, 13608-13609.
1,2-Addition, Epoxidation, Oxygen, Pinacol Rearrangement