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An α‐difluoroalkylation of benzyl amines with trifluoromethylarenes is disclosed herein. This protocol is characterized by its operational simplicity, excellent chemoselectivity and broad scope—even with advanced synthetic intermediates—, thus offering a new entry point to medicinally‐relevant α‐difluoroalkylated amines from simple, yet readily accessible, precursors. [ABSTRACT FROM AUTHOR]

A vinylogous aldol‐type reaction of allylazaarenes and aldehydes is disclosed that affords a series of chiral γ‐hydroxyl‐α,β‐unsaturated azaarenes in moderate to excellent yields with high to excellent regio‐ and enantioselectivities. With (R,RP)‐TANIAPHOS and (R,R)‐QUINOXP* as the ligand, the carbon‐carbon double bond in the products is generated in (E)‐form. With (R)‐DTBM‐SEGPHOS as the ligand, (Z)‐form carbon‐carbon double bond is formed in the major product. In this vinylogous reaction, aromatic, α,β‐unsaturated, and aliphatic aldehydes are competent substrates. Moreover, a variety of azaarenes, such as pyrimidine, pyridine, pyrazine, quinoline, quinoxaline, quinazoline, and benzo[d]imidazole are well‐tolerated. At last, the chiral vinylogous product is demonstrated as a suitable Michael acceptor towards CuI‐catalyzed nucleophilic addition with organomagnesium reagents. [ABSTRACT FROM AUTHOR]

1,2‐Bisphosphines have been identified as one class of important and powerful chiral ligands in asymmetric catalysis with transition metals. Herein, a copper(I)‐catalyzed asymmetric hydrophosphination of α,β‐unsaturated phosphine sulfides was developed with the assistance of "soft–soft" interaction between copper(I)‐catalyst and the phosphine sulfide moiety, which afforded 1,2‐bisphosphine derivatives with diversified electronic nature and steric hindrance in high to excellent yields with high to excellent enantioselectivity. Moreover, the challenging catalytic asymmetric hydrophosphination/protonation reaction was achieved with excellent enantioselectivity. Strikingly, the dynamic kinetic resolution of racemic diarylphosphines was also successfully carried out with high to excellent diastereo‐ and enantioselectivities. Interestingly, the nucleophilic copper(I)‐diphenylphosphide species was characterized by 31P NMR spectrum and mass spectrum. At last, three products were transformed to chiral 1,2‐bisphosphines, which were employed as ligands in Rh‐catalyzed asymmetric hydrogenation of α‐amino‐α,β‐unsaturated ester. The α‐amino acid derivative was produced in high enantioselectivity, which demonstrated the utility of the present methodology. [ABSTRACT FROM AUTHOR]