Hydroalkylation of styrenes enabled by boryl radical mediated halogen atom transfer

Abstract

In this study, we present an inexpensive, stable, and easily available boryl radical source (BPh₄Na) employed in a Halogen Atom Transfer (XAT) methodology. This mild and convenient strategy unlocks the use of not only alkyl iodides as radical precursors but also of the more challenging alkyl and aryl bromides to generate C-centered radicals. The generated radicals were further engaged in the anti-Markovnikov hydroalkylation of electronically diverse styrenes, therefore achieving the formation of C(sp³)-C(sp³) and C(sp³)-C(sp²) bonds. A series of experimental and computational studies revealed the prominent role of BPh₄Na in the halogen abstraction step.