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Updated: Mar 24, 2026

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
Lithium/Element Exchange as an Efficient Tool for Accessing Atropo-enriched Biaryls via Arynes
Armen Panossian1, Frédéric R Leroux2
1CNRS/University of Strasbourg UMR CNRS 7509 - Laboratoire de Chimie, Moléculaire, ECPM, 25 Rue Becquerel, 67087 Strasbourg Cedex 2, France.
Abstract:
This account documents the development of transition metal-free, aryne-mediated aryl-aryl coupling, the 'ARYNE coupling', which began in 2001 in Lausanne. ortho,ortho'-Di-, tri- and even tetrasubstituted biphenyls have now become accessible on a multi-gram scale. The reaction is perfectly regioselective and the obtained polybromobiphenyls can be submitted to regioselective bromine/lithium interconversions. The access to enantiopure biphenyls is now possible using enantiopure sulfoxides as chiral auxiliaries, which allow for subsequent chemoselective sulfoxide/metal exchange on each atropo-diastereoisomer with configurational stability of the intermediate biaryllithiums. Direct atropo-diastereoselective ARYNE coupling has been reported more recently.
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