Catalytic Enantioselective Synthesis of C–N Atropisomeric Heterobiaryls

Abstract Molecules containing an atropisomeric C–N biaryl axis are gaining increasing attention in catalytic and medicinal chemistry. Despite this rising interest, relatively few approaches towards their enantioselective synthesis have been reported. Here we review these approaches, with a focus on the mechanism of asymmetric induction. Some common themes emerge: Brønsted acid catalysed cyclo-condensation palladium-catalysed ring-closure most successful approaches. Meanwhile, more direct but challenging axial bond formation strategy remains its infancy, just two reports to-date. We hope will inform inspire other researchers to develop new creative important chemical motif. 1 Introduction 2 Cyclo-Condensation 3 Proximal Bond Formation 4 Desymmetrisation Intact Axes 5 ortho-C–H Functionalisation 6 Cycloaddition 7 Axial 8 Atropisomeric N–N Axes: An Emerging Class Heterobiaryls 9 Conclusion Outlook