Photochemical addition of cyclic ethers/acetals to olefins using BuOO Bu: Synthesis of masked ketones/aldehydes and diols

A fast photochemical C–C bond formation between cyclic ethers/acetals and olefins using di-tert-butyl peroxide (DTBP) was developed. This method provides easy access to 2-substituted cyclic ethers, and 2- or 4-substituted cyclic acetals. Acyl/formyl groups or diols can be obtained by the hydrolysis of the 2- or 4-substituted cyclic acetals, respectively. The reactions proceeded at room temperature and gave the expected products in good to excellent yields; efficient reactions were completed within 0.5 h at room temperature in >95% yield.