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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Synthesis of (+)-Tacamonine via Stereoselective Radical Cyclization
Myles W Smith1, Jasmin Ferreira1, Roger Hunter1
1Department of Chemistry , University of Cape Town , Rondebosch 7701 , Cape Town , South Africa.
Abstract:
A concise, asymmetric synthesis of the indole alkaloid (+)-tacamonine is reported involving a stereoselective radical cyclization of a 1-phenylsulfanyl tetrahydro-β-carboline bearing a pendant enoate ester side chain as a key step. In this process, a single stereocenter in the side chain allows for the formation of two stereocenters of the natural product in a highly diastereoselective fashion. Computational investigations of this key cyclization support the experimentally observed outcome and shed light on the factors impacting its stereoselectivity.
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