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We developed the remote selective C−H bromination for the synthesis of C4′‐brominated biarylphosphine oxides using FeBr3 as a brominating reagent. C3′‐Brominated products were obtained in reactions with substrates bearing a 2,4,6‐triisopropyl substituent on the bottom ring. Moreover, direct access to C5‐chlorinated peri‐substituted(1‐naphthalenyl)phosphines is developed using FeCl3 as a chlorinating reagent. These halogenated compounds can be utilized for cross‐coupling reactions to construct functionalized phosphine oxides. [ABSTRACT FROM AUTHOR]

The construction of atropisomers with 1,2-diaxes, while maintaining high enantiocontrol, presents a significant challenge due to the dynamic nature of steric hindrance at ortho-aryl substituents. Although various catalytic asymmetric methods have been developed for accessing axially chiral arylpyrroles, the synthesis of axially chiral arylpyrroles with 1,2-diaxes in a catalytic asymmetric manner has remained rare. Herein, the authors report the synthesis of diverse axially chiral arylpyrroles with 1,2-diaxes, and C-C and C-N axes through copper-catalysed asymmetirc [4 + 1] annulation of yne-allylic esters with arylamines via a remote stereocontrol strategy. This approach provides facile access to a broad range of heterobiaryl atropisomers (67 examples) in excellent enantioselectivities, each bearing one or two C-C/C-N axes, demonstrating its versatility and efficiency. The utility of this methodology is further highlighted by the transformation of the product into chiral phosphine ligand, and chiral thioureas for the use in asymmetric catalysis., (© 2024. The Author(s).)