Retention of Configuration in Photolytic Decarboxylation of Peresters to Form Chiral Acetals and Ethers

Peresters generate ethers in good yields when photolyzed in the absence of solvent using short wavelength UV light. At −78 °C or below, the process proceeds predominantly with retention of configuration at the site adjacent to the carbonyl where the decarboxylation occurs, but increase in temperature results in loss of stereochemical control. Chiral acyclic acetals can be prepared using precursors derived from tartaric or malic acids.