Samarium(II) iodide-mediated intramolecular conjugate additions of alpha,beta-unsaturated lactones
Gary A Molander1, David J St Jean
1Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA. gmolandr@sas.upenn.edu
Abstract:
Samarium(II) iodide, in the presence of catalytic amounts of nickel(II) iodide, has been used to promote intramolecular conjugate additions of alkyl halides onto alpha,beta-unsaturated lactones. This process has been shown to be applicable to a number of alpha,beta-unsaturated lactones, including tetrasubstituted olefins, and has been demonstrated to be quite general for the formation of saturated bicyclic and tricyclic lactones. The method presented herein provides a mild, efficient process to form structurally complex lactones from simple precursors.
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