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An iridium‐catalyzed remote site‐switchable hydroarylation of alkenes was reported, delivering the products functionalized at the subterminal methylene and terminal methyl positions on an alkyl chain controlled by two different ligands, respectively, in good yields and with good to excellent site‐selectivities. The catalytic system showed good functional group tolerance and a broad substrate scope, including unactivated and activated alkenes. More importantly, the regioconvergent transformations of mixtures of isomeric alkenes were also successfully realized. The results of the mechanistic studies demonstrate that the reaction undergoes a chain‐walking process to give an [Ar−Ir−H] complex of terminal alkene. The subsequent processes proceed through the modified Chalk–Harrod‐type mechanism via the migratory insertion of terminal alkene into the Ir−C bond followed by C−H reductive elimination to afford the hydrofunctionalization products site‐selectively. [ABSTRACT FROM AUTHOR]

The design and synthesis of chiral ligands plays an important role in asymmetric catalytic reactions. Over the past decades, various types of chiral phosphine‐oxazolines (PHOX ligands) have been developed and have greatly advanced the field of asymmetric catalysis. Novel chiral PHOX ligand with an axis‐unfixed biphenyl backbone, developed by our group, have shown interesting coordination behavior and excellent chiral inducing ability in various transition‐metal‐catalyzed asymmetric reactions. This personal account focuses on our developed axis‐unfixed biphenylphosphine‐oxazoline ligand (BiphPHOX), including an overview of its design and applications, which will provide inspiration for the exploration of novel ligands and related reactions. [ABSTRACT FROM AUTHOR]

Axis-unfixed, biphenylphosphine-oxazoline, iridium, asymmetric hydrogenation, alkenes Cover Picture: Axis-Unfixed Biphenylphosphine-Oxazoline Ligands: Design and Applications in Asymmetric Catalytic Reactions (Chem. Rec. 10/2023) Keywords: axis-unfixed; biphenylphosphine-oxazoline; iridium; asymmetric hydrogenation; alkenes EN axis-unfixed biphenylphosphine-oxazoline iridium asymmetric hydrogenation alkenes 1 1 1 10/16/23 20231001 NES 231001 The Front Cover depicts the applications of axis-unfixed biphenylphosphine-oxazoline ligands, which were designed based on dihedral angle regulation, in transition-metal-catalyzed asymmetric hydrogenation, asymmetric allylic substitution, and asymmetric addition reactions. [Extracted from the article]