Molecular-Oxygen-Mediated Multicomponent Oxidative Cyclization: Synthesis of Tertiary-Alcohol-Unit-Bearing <i>N</i>-Heterocycles via Transforming C–H to C–OH Bonds

We developed a molecular-oxygen-mediated multicomponent oxidative cyclization strategy to synthesize <i>N</i>-heterocycles containing tertiary alcohol units via the formation of key C-OH bonds and quaternary carbon centers. This formal [3 + 2 + 1] annulation offers a green and sustainable alternative for the <i>de novo</i> C-OH bond formation, using O₂ as both the oxidant and oxygen source under metal- and catalyst-free conditions. Notably, continuous [1,5]-hydrogen transfer together with excess alcohols promotes the formation of C-OH-bearing products. Additionally, the generation of quaternary carbon centers inhibits the conversion of C-OH bonds to C═O bonds, thus stabilizing the desired products.