Photocatalytic Alkylation of C(sp3)-H Bonds Using Sulfonylhydrazones

The ability to construct C(sp(3))-C(sp(3)) bonds from easily accessible reagents is a crucial, yet challenging endeavor for synthetic organic chemists. Herein, we report the realization of such a cross-coupling reaction, which combines N-sulfonyl hydrazones and C(sp(3))-H donors through a diarylketone-enabled photocatalytic hydrogen atom transfer and a subsequent fragmentation of the obtained alkylated hydrazide. This mild and metal-free protocol was employed to prepare a wide array of alkyl-alkyl cross-coupled products and is tolerant of a variety of functional groups. The application of this chemistry further provides a preparatively useful route to various medicinally-relevant compounds, such as homobenzylic ethers, aryl ethyl amines, beta-amino acids and other moieties which are commonly encountered in approved pharmaceuticals, agrochemicals and natural products.