Synthesis of Distal 1,4-Diaxial Atropisomers: CPA-Catalyzed Atroposelective (3 + 3)-Annulation via a Desymmetrization...

The synthesis of atropisomeric biaryls has emerged as a significant frontier in organic chemistry. While notable advances have been achieved in the synthesis of atropisomers with a single chiral axis, the catalytic stereoselective assembly of atropisomers bearing multiple chiral axes remains a formidable challenge. Herein, we report a chiral phosphoric acid (CPA)-catalyzed atroposelective (3 + 3)-annulation between readily accessible propargylic alcohols and symmetric biaryltriols through a desymmetrization strategy, preparing a diverse array of distal 1,4-diaxial atropisomers possessing functionalized 2H-chromen and biaryldiol fragments. Notably, the protocol enables the divergent synthesis of two new sets of stereoisomers of distal 4,8-binaphthalen-1-yl-2H-chromenediols (BINCOLs) from identical symmetric triol precursors. The 1,4-diaxial BINCOLs demonstrate considerable utility as promising ligands in asymmetric catalysis, as evidenced by the successful application in Cu-catalyzed enantioselective C-H thiolation of ferrocene carboxamide. Furthermore, the 1,4-diaxial BINCOLs exhibit an aggregation-induced emission effect, highlighting their potential as a new class of polycyclic aromatic AIEgens.