Enantioselective Spirocyclopropanation of para-Quinone Methides Using Ammonium Ylides.

Org Lett

Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstr. 69, 4040 Linz, Austria.

Published: May 2017

The use of Cinchona alkaloid-based chiral ammonium ylides allows for the first highly enantioselective and broadly applicable spirocyclopropanation reactions of para-quinone methides. This strategy provides a straightforward protocol toward the chiral spiro[2.5]octa-4,7-dien-6-one skeleton, which is a frequently found structural motif in important biologically active molecules.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420312PMC
http://dx.doi.org/10.1021/acs.orglett.7b00869DOI Listing

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