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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Dearomatisation approaches to spirocyclic dienones via the electrophilic activation of alkynes
Aimee K Clarke1, John T R Liddon1, James D Cuthbertson1
1University of York, Heslington, York YO10 5DD, UK. richard.taylor@york.ac.uk william.unsworth@york.ac.uk.
Abstract:
Two complementary dearomatising spirocyclisation protocols to generate spirocyclic dienones from anisole and phenol-tethered ynones are described, each proceeding via electrophilic alkyne activation. The first approach focuses on the spirocyclisation of para-substituted anisoles using either SnCl2·2H2O or Cu(OTf)2. The second approach, which enables the spirocyclisation of both ortho- and para-substituted phenols, uses silica-supported AgNO3 to generate similar scaffolds with much greater efficiency. Initial asymmetric studies are also outlined.
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