An Enyne Cope Rearrangement Enables Polycycloalkane Synthesis from Readily Available Starting Materials
Sarah K Scott1, Alexander J Grenning1
1Department of Chemistry, University of Florida, PO Box 117200, Gainesville, FL, 32611-7200, USA.
Abstract:
Cyclohexanone-derived Knoevenagel adducts (cyclohexylidenemalononitriles) and two different propargyl electrophiles serve as carbon sources for assembling diverse 6/7/5 tricycloalkanes, a common terpenoid framework. The sequence involves three unique reactions: 1) deconjugative propargylation, 2) one-pot enyne Cope rearrangement/deconjugative propargylation, and 3) an allenic Pauson-Khand reaction.
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