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The atroposelective synthesis of atropisomers with vicinal diaxes remains rare and challenging, due to the steric influence between the two axes and their unique topology. Herein, we disclose a single‐step construction of atropisomers with vicinal C−C and C−N chiral diaxes by cyclopentadiene (Cp)‐free cobalt‐catalyzed intramolecular atroposelective C−H annulation, providing the desired diaxial atropisomers of unique structures with decent stereocontrols of both axes (up to >99 % ee and 70 : 1 dr). The optically pure products bearing fluorophores show circular polarized luminescence (CPL) properties, being candidate materials for potential CPL applications. Atropisomerization experiments and density function theory (DFT) calculations are conducted to study the rotational barriers and rotation pathways of the diaxes. [ABSTRACT FROM AUTHOR]

Inherently chiral calixarenes have garnered significant attention due to their distinctive properties, yet the development of efficient catalytic asymmetric synthesis methods remains a critical challenge. Herein, we report the asymmetric synthesis of calix[4]arenes featuring inherent or both inherent and axial chirality via a cobalt‐catalyzed C−H activation/annulation strategy in high yield with excellent enantio‐ and diastereoselectivity (up to >99 % ee and >20 : 1 dr). Electrooxidation was also suitable for this transformation to obviate the sacrificial metal oxidants, underscoring the environmentally friendly potential of this approach. A key octahedral cobaltacycle intermediate was synthesized and characterized, providing valuable insights into the mode of enantio‐ and diastereocontrol of this protocol. Noteworthy photoluminescence quantum yields of up to 0.94 were measured, underscoring the potential of these compounds in the domain of organic fluorescent materials. [ABSTRACT FROM AUTHOR]