Radical α-C-H Cyclobutylation of Aniline Derivatives.

A catalytic system has been developed for the direct alkylation of α-C-H bonds of aniline derivatives with strained C-C σ-bonds. This method operates through a photoredox mechanism in which oxidative formation of aminoalkyl radical intermediates enables addition to a bicyclobutane derivative, giving rise to α-cyclobutyl N-alkylaniline products. This mild system proceeds through a redox- and proton-neutral mechanism and is operational for a range of substituted arylamine derivatives.