A one carbon linchpin for Rh(iii)-catalyzed, C(sp3)-directed C-H annulation.

We disclose a new platform for C(sp3)-directed C-H annulations to generate valuable heterocycles from readily available starting materials. A commercially available one carbon linchpin is leveraged to access alkyl boron species from simple anilines. Rhodium-catalyzed C(sp3) transmetallation from this key intermediate provides a C-Rh bond appropriately positioned for ortho-C-H activation, enabling formation of a C,C-rhodacycle. With the addition of a variety of alkyne coupling partners, diverse dihydroquinolines are synthesized.