Directed Diastereoselective Cyclopropanation and Epoxidation of Alkenyl Cyclopropyl Carbinol Derivatives
Anthony Cohen1, Yogesh Siddaraju1, Ilan Marek1
1Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa 3200009, Israel.
Abstract:
We report the directed diastereoselective Simmons-Smith cyclopropanation and vanadium-catalyzed epoxidation reactions of alkenyl cyclopropyl carbinol derivatives. The reaction furnished densely substituted stereodefined bicyclopropanes and cyclopropyl oxiranes as a single diastereomer in each case. The remarkable selectivity is obtained thanks to the rigidity of the cyclopropyl core, allowing diastereoselective reactions on the alkenyl moiety. This emphasizes the uniqueness of the cyclopropyl ring as a central platform in stereoselective synthesis.
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