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Updated: Apr 25, 2026

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
1,3-Halogen migration as an entry to aryl coppers from an unintuitive starting material
R J Van Hoveln1, S C Schmid, J M Schomaker
1Department of Chemistry, University of Wisconsin, 1101 University Ave., Madison, Wisconsin 53706, USA. schomakerj@chem.wisc.edu.
Abstract:
A copper(I) catalyzed 1,3-halogen migration/borylation migrates a bromine from an sp(2) carbon to a benzylic carbon with concomitant borylation of the aryl-bromine bond. This transformation proceeds via an aryl copper intermediate which can be accessed independently and then trapped with electrophiles. As such, copper-catalyzed 1,3-halogen migration provides unique and mild access to an aryl copper species that allows for rapid aromatic functionalization from an unconventional starting material.
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