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Herein, the use of economically and environmentally friendly bis(pinacolato)diboron (B2Pin2) is described as a non‐metallic reductant in mediating Ni‐catalyzed C(sp3)–C(sp2) 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 B2Pin2 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 B2Pin2 can sever as a reductant to reduce NiII to Ni0. This mechanistic insight may inspire the development of new reductive bond‐forming methodologies that can otherwise be difficult to achieve with a metal reductant. [ABSTRACT FROM AUTHOR]

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 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. [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]

Good's syndrome (GS) is characterized by thymoma combined with adult‐onset immunodeficiency. Diffuse panbronchiolitis (DPB) is a chronic inflammatory airway disease, which predominantly affects East Asians. Japanese scholars have reported extensively about GS combined with DPB or DPB‐like pulmonary manifestation. However, such reports are rare in China. We report here a case of GS in China with DPB as the prominent manifestation and carry out a literature review accordingly. Our review indicates that in adults with DPB‐like clinical manifestations, thymic lesions should be excluded and related immune function tests should be performed to exclude GS to avoid missed diagnosis and misdiagnosis. [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]

Asymmetric functionalizations of α‐sulfanyl cyclic ketones were realized via chiral phosphoric acid catalyzed enantioselective addition reactions with aldimines, azodicarboxylates and allenamides. A series of chiral organosulfur compounds possessing sulfur‐containing tetrasubstituted stereocenters were accessed via these methods, with excellent regioselectivities and high stereoselectivities. [ABSTRACT FROM AUTHOR]

An AgI-mediated ethoxycarbonyldifluoromethylation of isocyanides has been developed. This radical cascade reaction involves the addition of difluoromethylene radical to the isocyanide functionality, and subsequent homolytic aromatic substitution to give difluoromethylated phenanthridines with a good functional-group tolerance. [ABSTRACT FROM AUTHOR]

The first AgI-mediated C-H ethoxycarbonyl difluoromethylation with TMSCF2COOEt (TMS = trimethylsilyl) has been developed. The radical difluoromethylation proceeds smoothly to give the difluoromethylated arenes in moderate to high yields with Friedel-Crafts-type regioselectivity. Mechanistic studies indicate that the innate C-H difluoromethylation proceeds through an electrophilic radical-type pathway. [ABSTRACT FROM AUTHOR]

A simple AgI-mediated direct difluoromethylation reaction of activated alkenes by using TMSCF2COOEt (TMS = trimethylsilyl) under mild reaction conditions has been described. This reaction tolerates a variety of functional groups and allows for a highly efficient synthesis of various difluoro-containing oxindoles. Mechanistic investigations indicate that a difluoromethyl radical initiated the cascade sequence by undergoing an addition reaction to the alkene. [ABSTRACT FROM AUTHOR]