Temporary Generation of a Cyclopropyl Oxocarbenium Ion Enables Highly Diastereoselective Donor-Acceptor Cyclopropane Cycloaddition.

Angew Chem Int Ed Engl

Fakultät für Chemie, Institut für Organische Chemie, Universität Wien, Währinger Straße 38, 1090, Wien, Austria.

Published: June 2016

A novel formal [3+2] cycloaddition of cyclopropylacetals and aldehydes was developed, and the resulting trisubstituted tetrahydrofurans display three new chiral centers formed with highly diastereoselectivity. This method is stereocomplementary to most previously reported cycloadditions of malonate diesters, relies on the transient generation of cyclopropyl oxocarbenium ions, proceeds under mild conditions, and is based on the concept of temporary activation of an otherwise inert protecting group.

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http://dx.doi.org/10.1002/anie.201601340DOI Listing

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