Hydrido-Cobalt Complexes for the Chemo- and Regioselective 1,2-Silylative Dearomatization of N -Heteroarenes.

We describe an efficient regio- and chemoselective dearomatization of -heteroarenes using hydrido-cobalt catalysts. Reactions were performed under mild conditions on a wide range of -heteroarenes leading exclusively to the silyl-1,2-dihydroheteroarene. Various quinolines and pyridines bearing electron-donating and electron-withdrawing substituents are compatible with this methodology. DFT calculations, NMR spectroscopic studies, and X-ray diffraction analysis underlined the importance of a second silane for the final step of the reaction.