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The precise control of the regioselectivity in the transition metal‐catalyzed migratory hydrofunctionalization of alkenes remains a big challenge. With a transient ketimine directing group, the nickel‐catalyzed migratory β‐selective hydroarylation and hydroalkenylation of alkenyl ketones has been realized with aryl boronic acids using alkyl halide as the mild hydride source for the first time. The key to this success is the use of a diphosphine ligand, which is capable of the generation of a Ni(II)‐H species in the presence of alkyl bromide, and enabling the efficient migratory insertion of alkene into Ni(II)‐H species and the sequent rapid chain walking process. The present approach diminishes organosilanes reductant, tolerates a wide array of complex functionalities with excellent regioselective control. Moreover, this catalytic system could also be applied to the migratory hydroarylation of alkenyl azahetereoarenes, thus providing a general approach for the preparation of 1,2‐aryl heteroaryl motifs with wide potential applications in pharmaceutical discovery. [ABSTRACT FROM AUTHOR]

The use of molecular oxygen as the terminal oxidant in transition metal catalyzed oxidative process is an appealing and challenging task in organic synthetic chemistry. Here, we report a Ni‐catalyzed hydroxylarylation of unactivated alkenes enabled by a β‐diketone ligand with high efficiency and excellent regioselectivity employing molecular oxygen as the oxidant and hydroxyl source. This reaction features mild conditions, broad substrate scope and incredible heterocycle compatibility, providing a variety of β‐hydroxylamides, γ‐hydroxylamides, β‐aminoalcohols, γ‐aminoalcohols, and 1,3‐diols in high yields. The synthetic value of this methodology was demonstrated by the efficient synthesis of two bioactive compounds, (±)‐3′‐methoxyl citreochlorol and tea catechin metabolites M4. [ABSTRACT FROM AUTHOR]

Here, we report the first example of Ni‐catalyzed asymmetric hydrosilylation of 1,1‐disubstituted allenes with high level of regioselectivities and enantioselectivities. The key to achieve this stereoselective hydrosilylation reaction was the development of the SPSiOL‐derived bisphosphite ligands (SPSiPO). This protocol features broad substrate scope, excellent functional group, and heterocycle tolerance, thus provides a versatile method for the construction of enantioenriched tertiary allylsilanes in a straightforward and atom‐economic manner. DFT calculations were performed to reveal the reaction mechanism and the origins of the enantioselectivity. [ABSTRACT FROM AUTHOR]

Reported here is the discovery of a redox‐neutral NiII/NiII catalytic cycle which is capable of the linear‐selective hydroarylation of unactivated alkenes with arylboronic acids for the first time. This novel catalytic cycle, enabled by the use of an electron‐rich diimine ligand, features broad substrate scope, and excellent functional‐group and heterocycle compatibility under mild reaction conditions in the absence of additional oxidants and reductants. Mechanistic investigations using kinetic analysis and deuterium‐labelling experiments revealed the protonation to be the rate‐determining step in this redox‐neutral catalysis, and the reversible chain‐walking nature of the newly developed diimine‐Ni catalyst. [ABSTRACT FROM AUTHOR]