Nickel-Catalyzed Switchable Site-Selective Alkene Hydroalkylation by Temperature Regulation.

Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel-catalyzed switchable site-selective alkene hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate. This protocol allows the convenient synthesis of α- and β-branched protected amines, both of which are important to the fields of pharmaceutical chemistry and biochemistry. In addition, enantioenriched β-branched alkylamines can be accessed in a catalytic asymmetric variant. Preliminary mechanistic studies indicate that the formation of a more stable nickelacycle provides the driving force of migration. The thermodynamic and kinetic properties of different reduction elimination intermediates are responsible for the switchable site-selectivity.