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Herein, the use of economically and environmentally friendly bis(pinacolato)diboron (B 2 Pin 2 ) is described as a non-metallic reductant in mediating Ni-catalyzed C(sp 3 )-C(sp 2 ) reductive cross-coupling of alkyl electrophiles with aryl/vinyl halides. This method exhibits excellent suitability for heteroaryl halides and alkyl halides/Katritzky salts. The present study is compatible with an in situ halogenation of alcohol method, allowing for selective mono-functionalization of diols and bio-relevant alcohols (e.g., carbohydrates). The use of B 2 Pin 2 shows potential for easy scalability without introducing additional metal impurities into the products. It is observed for the first time in the realm of cross-electrophile coupling chemistry that B 2 Pin 2 can sever as a reductant to reduce Ni II to Ni 0 . This mechanistic insight may inspire the development of new reductive bond-forming methodologies that can otherwise be difficult to achieve with a metal reductant., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

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., (© 2023 Wiley-VCH GmbH.)

An efficient silver-promoted decarboxylative gem-difluoromethylenation of aryl- or alkyl-substituted α,β-unsaturated carboxylic acids with readily available benzo-1,3-diazolic difluoromethyl bromides has been developed. This convenient transformation demonstrated good functional-group tolerability and broad substrate scope, and afforded the allylic difluorides in good to excellent yields with exclusive E-stereoselectivity under mild reaction conditions., (© 2022 Wiley-VCH GmbH.)

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., (© 2022 Wiley-VCH GmbH.)

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., (© 2020 Wiley‐VCH GmbH.)