Thermal decomposition of the tert-butyl perester of thymidine-5′-carboxylic acid. Formation and fate of the pseudo-C4′ radical

Thermal decomposition of the tert-butyl perester of thymidine-5′-carboxylic acid carried out at 85 °C in different solvents affords the tert-butylacetal , deriving from in cage decomposition, and pseudo C4′ radicals . Radicals can be reduced to by hydrogen atom abstraction from thiol (thiophenol or glutathione) or THF, or can be oxidized to cations by dioxygen or perester itself. Cations are stereoselectively trapped by the nucleophilic solvent (tert-butanol, methanol, water) to give acetals .