We report the preparation of axially stereoenriched biphenyls by the coupling of in situ generated aryllithiums and arynes using chiral oxazoline auxiliaries. The design of the aryne precursors, the choice of oxazoline and the reaction conditions were key to accessing the desired, highly substituted, atropisomerically enriched biarylic products. In one case, the two atropo‐diastereomers could be obtained in isomerically pure form by column chromatographic separation and their absolute configurations established by X‐ray crystallography. The stereoselectivity of the reaction seems to be governed by subtle parameters.

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The formal synthesis of the two enantiomers of a natural, axially chiral biaryl, steganacin, is reported. The previously developed atropo‐diastereoselective coupling of an aryne and an aryllithium (“aryne coupling”) allows for this synthesis. In each step, the axial configuration of the biaryl could be maintained. The key intermediate, identified previously, was accessed without using transition metals, which demonstrates the potential of the aryne coupling reaction as a complementary or alternative to transition‐metal‐catalyzed coupling reactions.

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For the first time, the challenging atropo-enantioselective coupling of in-situ generated arynes and aryllithiums in the presence of a chiral ligand of lithium was investigated. This preliminary study demonstrates the feasibility of this concept, by affording enantioenriched axially chiral biaryls even in the case of products showing a high degree of steric congestion around the newly created arylÀ aryl bond.