Regenerable Antioxidants-Introduction of Chalcogen Substituents into Tocopherols

To improve the radical‐trapping capacity of the natural antioxidants, alkylthio‐, alkylseleno‐, and alkyltelluro groups were introduced into all vacant aromatic positions in β‐, γ‐ and δ‐tocopherol. Reaction of the tocopherols with electrophilic chalcogen reagents generated by persulfate oxidation of dialkyl dichalcogenides provided convenient but low‐yielding access to many sulfur and selenium derivatives, but failed in the case of tellurium....