Abstract
The synthesis of D,L‐α‐tocopherol from trimethylhydroquinone and isophytol using the Brønsted acidic SO3H‐functionalized ionic liquids as catalysts was explored. The catalytic activities of the SO3H‐functionalized ionic liquids were dependent on their anions. The yield of D,L‐α‐tocopherol also depended on the solvent, which was the reaction medium. A yield of 94.3% was obtained using the SO3H‐functionalized ionic liquid with [BF4 −] anion as catalyst in propylene carbonate/heptane. The reaction mixture exhibited good biphasic behaviors, so that the produced D,L‐α‐tocopherol could be separated by decantation. The SO3H‐functionalized ionic liquids could be reused after the removal of water.