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Metal‐hydride‐catalyzed migratory functionalization of alkenes witnessed extensive development in the past few years. However, the asymmetric version of this reaction has remained largely underdeveloped owing to the difficulty in simultaneous control of both regio‐ and stereoselectivity. In addition, exploring the wider alkene substrate scope to enable more synthetically valuable applications represents another challenge in this field. In this context, a nickel‐catalyzed asymmetric hydrocyanation of internal alkenes involving a chain‐walking process is demonstrated. The reaction exhibits excellent regio‐ and enantioselectivity, proceeds under mild reaction conditions, and delivers benzylic nitriles in high yields. Even α,ω‐diaryl internal alkenes, which are known to be one of the most challenging substrates of this type, could be successfully converted to the desired products with good regio‐ and stereoselectivity by modifying the electronic and steric effects. Theoretical calculations suggest that the η3‐benzyl coordination mode and the aryl substituent (3,5‐(OMe)2C6H3) on the diphosphite ligand are both key factors in regulating regio‐ and enantioselectivity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Key Scientists The construction of acyclic quaternary carbon stereocenters, which are ubiquitous in many bioactive compounds, pharmaceuticals and natural products, has been a long persuit in synthetic organic chemistry. Among numerous methods, enantioselective nickel‐catalysis has attracted incremental attention in recent years. This review summarizes the recent development in the asymmetric strategies, research progress, mechanistic investigations for the generation of acyclic quaternary carbon stereocenters via enantioselective nickel catalysis.In 2006, the Zhou group and RajanBabu group realized the nickel‐catalyzed enantioselective hydrovinylation of α‐substituted styrenes and ethylene to construct acyclic quaternary carbon stereocenters (QCSs) by using spiro‐ and binaphthyl phosphoramidite ligands, respectively. In 2016, Watson developed a nickel‐catalyzed Suzuki‐Miyaura arylation to generate acyclic QCSs via chirality transfer reaction. In 2017, the Feng and the Fu group developed nickel‐catalyzed enantioselective conjugated/Michael additions to build acyclic QCSs, respectively. In 2020, the Fang group made the first success in the construction of QCSs by nickel‐catalyzed hydrocyanation of alkenes and allenes. In 2021, Gregory C. Fu and co‐workers disclosed a nickel‐catalyzed enantioselective α‐functionalization of carbonyl compounds that could form acyclic QCSs. At the same time, the Shi group constructed chiral acyclic QCSs via nickel‐catalyzed functionalization of alkenes. In 2023, Kleij and co‐workers applied a new strategy for Ni‐catalyzed regio‐ and enantioselective homoallylic coupling to construct acyclic QCSs. In the same year, Tao and co‐workers demonstrated a novel strategy that is dinickel‐catalyzed enantioselective α‐alkylation of carbonyl compounds with alkyl iodides. [ABSTRACT FROM AUTHOR]

Copper-catalyzed oxidative intramolecular cyclization of o -alkylated anilines via cleavage of C(sp 3 )-H and N-H bonds for the production of indolines is described. This approach provides a straightforward strategy for the synthesis of nitrogen-containing heterocyclic compounds through the functionalization of unactivated C(sp 3 )-H bonds with high site selectivity. The present catalytic system shows high preference for functionalization of unactivated C(sp 3 )-H bonds over C(sp 2 )-H bonds, leading to C-N bond formation.

The Iodine-mediated oxidative intramolecular amination of anilines via cleavage of unactivated (sp 3 )C-H and N-H bonds for the production of indolines is described. This transition-metal-free approach provides a straightforward strategy for producing (sp 3 )C-N bonds for use in the preferential functionalization of unactivated (sp 3 )C-H bonds over (sp 2 )C-H bonds. The reaction could be performed on a gram scale for the synthesis of functionalized indolines.