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Axially chiral diaryl ethers are a type of unique atropisomers bearing two potential axes, which have potential applications in a variety of research fields. However, the catalytic enantioselective synthesis of these diaryl ether atropisomers is largely underexplored when compared to the catalytic asymmetric synthesis of biaryl or other types of atropisomers. Herein, we report a highly efficient catalytic asymmetric synthesis of diaryl ether atropisomers through an organocatalyzed enantioselective desymmetrization protocol. The chiral phosphoric acid‐catalyzed asymmetric electrophilic aromatic aminations of the symmetrical 1,3‐benzenediamine type substrates afforded a series of diaryl ether atropisomers in excellent yields and enantioselectivities. The facile construction of heterocycles by the utilizations of the 1,2‐benzenediamine moiety in the products provided access to a variety of structurally diverse and novel azaarene‐containing diaryl ether atropisomers. [ABSTRACT FROM AUTHOR]

An efficient approach for asymmetric synthesis of planar‐chiral macrocycles (paracyclophanes) has been disclosed through enantioselective electrophilic aromatic aminations with azodicarboxylates enabled by chiral phosphoric acid catalysis. A wide range of chiral macrocycles bearing varied ring sizes (16 to 23‐membered) and functional group‐containing ansa chains were readily afforded using this method, with excellent yields and high enantioselectivities (23 examples, up to 99.5 : 0.5 er). Experimental studies and DFT calculations were performed to elucidate the mechanism and origin of stereoselectivities of these reactions. Preliminary utilization of the planar‐chiral macrocycle as chiral organocatalyst showcased the potential applications of these novel chiral skeletons. [ABSTRACT FROM AUTHOR]

The first kinetic resolution of hydroquinoline derivatives with α,α‐disubstitution has been achieved through asymmetric remote aminations with azodicarboxylates enabled by chiral phosphoric acid catalysis. Mechanistic studies suggest a monomeric catalyst pathway proceeding through rate‐ and enantio‐determining electrophilic attack promoted by a network of attractive non‐covalent interactions between the substrate and catalyst. Facile subsequent removal and transformations of the newly introduced hydrazine moiety enable these protocols to serve as powerful tools for asymmetric synthesis of N‐heterocycles with α,α‐disubstitution. [ABSTRACT FROM AUTHOR]

A series of cyclohexyl‐fused SPINOL‐derived phosphoric acids (Cy‐SPA) have been developed to catalyze the kinetic resolution of 2‐N‐acylamido tertiary allylic alcohols, providing access to chiral oxazolines bearing C‐2 alkyl substituents with high enantioselectivities (with s‐factors up to 153). Gram‐scale reaction with 1 mol% catalyst loading and transformations of the chiral products demonstrates the value of these methods. [ABSTRACT FROM AUTHOR]