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Diarylamines and related scaffolds are ubiquitous atropisomeric chemotypes in biologically active natural products. However, the catalytic asymmetric synthesis of these axially chiral compounds remains largely unexplored. Herein, we report that a BINOL‐derived chiral phosphoric acid (CPA) successfully catalyzed the atroposelective coupling of quinone esters and anilines through direct C−N bond formation to afford N‐aryl quinone atropisomers with an unprecedented intramolecular N−H−O hydrogen bond within a six‐membered ring in good yields and enantioselectivities with the quinone ester as both the electrophile and the oxidant. A gram‐scale experiment demonstrated the utility of this synthetic protocol. Moreover, this methodology provides a platform for the synthesis of structurally diverse secondary amine atropisomers by nucleophilic addition. [ABSTRACT FROM AUTHOR]

An enantioselective bifunctional squaramide‐catalyzed detrifluoroacetylative alkylation reaction has been developed under electrochemical conditions. The unified strategy based on this key tandem methodology has been divergently explored for the asymmetric synthesis of fluorine‐containing target molecules with good stereocontrol (up to 95 % ee). Furthermore, this asymmetric catalytic reaction combines the benefits of electrosynthesis and organocatalysis for the preparation of biologically relevant products containing C‐F tertiary stereogenic centers. [ABSTRACT FROM AUTHOR]

A highly enantioselective N-heterocyclic carbene (NHC) catalyzed formal [3+2] annulation of α,β-unsaturated aldehydes with azaaurones or aurone generating spiro-heterocycles has been developed. The protocol represents a unique NHC-activation-based approach to access spiro-heterocyclic derivatives bearing a quaternary stereogenic center with high optical purity (up to 95 % ee). [ABSTRACT FROM AUTHOR]