Synthesis of Tetralin and Chromane Motifs via Pd-Catalyzed Dual C(sp3)-H/C(sp2)-H Bond Activation.

A palladium-catalyzed intramolecular selective dual C-H bond activation between aliphatic β-C(sp3)-H and aromatic C(sp2)-H bonds of substituted sulfonamides is described. This methodology is highly compatible for building up privileged chromane and tetralin scaffolds in good to moderate yields from linear substrates through the intramolecular C-H cross-coupling reaction. Meanwhile, control experiments and metallacycle detection have been carried out to understand a feasible reaction mechanism for the present coupling reaction.