The Diels–Alder cycloaddition reaction of tetracyclone and functionalized, internal aryl acetylenes gave access to a number of bulky atropisomeric biaryls in good to excellent yield. The synthesis is convenient and yields the pure biaryls without tedious work-up and purification procedures. Exemplarily the atropisomers have been resolved via the diastereomers in an easy and efficient manner to yield
two-step route to axiallychiral biaryls is demonstrated. In a direct asymmetric cross-cyclotrimerization in the presence of a chiral cobalt(I) catalyst, axiallychiral biaryls bearing phosphoryl moieties have been prepared, and through indirect evidence the authors have been able to clarify the origin of the stereochemical induction and the nature of the central intermediate in the catalytic cycle. By subsequent