Synthesis of Cyclopentenones with C4-Quaternary Stereocenters via Stereospecific [3,3]-Sigmatropic Rearrangement and Applications in Total Synthesis of Sesquiterpenoids
Weiping Zhou, Arnaud Voituriez
Abstract
A cationic gold(I)-catalyzed asymmetric [3,3]-sigmatropic rearrangement of sulfonium leads after cyclization to cyclopentenones with a C4-quaternary stereocenter. Starting with simple vinyl sulfoxides and propargyl silane, numerous compounds were isolated with moderate to good yields and excellent enantiomeric excesses (26 examples). The application of this simple methodology allowed the efficient total synthesis of five natural sesquiterpenoids, including enokipodin A and B, hitoyopodin A, lagopodin A, and isocuparene-3,4-diol.
Topics & Concepts
StereocenterSulfoniumChemistrySigmatropic reactionPropargylStereospecificityTotal synthesisStereochemistryEnantiomerClaisen rearrangementCope rearrangementEnantioselective synthesisOrganic chemistryCatalysisSalt (chemistry)Synthetic Organic Chemistry MethodsCatalytic Alkyne ReactionsTraditional and Medicinal Uses of Annonaceae