Intramolecular Propargylic Ene Reaction of Benzyne En Route to Highly Functionalized Allenes and Allenamides

Abstract

A variety of highly functionalized allenes and allenamides are prepared by intramolecular propargylic ene reactions of benzynes. Specific benzyne precursors having a chlorodiisopropylsilyl group serve as platforms to link with various propargyl alcohols via a Si–O bond, thereby expanding the scope of this reaction. Also demonstrated is a complete transmission of point to axial chirality to give a chiral, non-racemic allenamide.

Key words

ene reaction - intramolecular reaction - benzyne - allenes - allenamides

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