Photo-Induced Pyridylic\nC(sp<sup>3</sup>)–H\nAlkylation with Unactivated Alkenes Enabled by Hydrogen Atom Transfer/Lewis\nAcid Cocatalysis

Radical\nhydroalkylation of alkenes represents an ideal\napproach\nfor C(sp<sup>3</sup>)–C(sp<sup>3</sup>) bond formation. However,\nradical precursors have been substantially limited due to the sluggish\nnature of less electrophilic carbon-centered radicals to participate\nin addition step toward unactivated alkenes. Herein, we demonstrate\nthat this inherent limitation can be overcome by the use of a Lewis\nacid catalyst. This cocatalytic system enables the hitherto elusive\nradical C(sp<sup>3</sup>)–C(sp<sup>3</sup>) bond formation\nbetween pyridylacetates and unactivated alkenes to generate medically\nrelevant valuable products. Computational studies support that the\nformation of a Lewis pair with the substrates is crucial to lower\nthe energy of the transition state for the rate-determining radical\naddition step.