Palladium and Iron Cocatalyzed Aerobic Alkene Aminoboration

Aminoboration of simple alkenes with nitrogen nucleophilesremainsan unsolved problem in synthetic chemistry; this transformation canbe catalyzed by palladium via aminopalladation followedby transmetalation with a diboron reagent. However, this catalyticprocess faces inherent challenges with instability of the alkylpalladium(II)intermediate toward & beta;-hydride elimination. Herein, we reporta palladium/iron cocatalyzed aminoboration, which enables this transformation.We demonstrate these conditions on a variety of alkenes and norborneneswith an array of common nitrogen nucleophiles. In the developed strategy,the iron cocatalyst is crucial to achieving the desired reactivityby serving as a halophilic Lewis acid to release the transmetalation-activecationic alkylpalladium intermediate. Furthermore, it serves as aredox shuttle in the regeneration of the Pd(II) catalyst by reactivationof nanoparticulate palladium.

Automated summary

In this study, the authors report a palladium/iron cocatalyzed aminoboration reaction that can successfully catalyze the aminoboration of simple alkenes. The iron cocatalyst plays a crucial role in releasing the transmetalation-active cationic alkylpalladium intermediate and acting as a redox shuttle in the regeneration of the Pd(II) catalyst.