We report Ir-catalyzed intramolecular silylation of secondary alkyl C–H bonds.(Hydrido) silyl ethers, generated in situ by dehydrogenative coupling of a tertiary or conformationally restricted secondary alcohol with diethylsilane, undergo regioselective silylation at a secondary C–H bond γ to the hydroxyl group. Oxidation of the resulting oxasilolanes in the same vessel generates 1, 3-diols. This method provides a strategy to synthesize 1, 3-diols ...