Cyclohexene is an easily available chemical raw material that can be prepared by selective hydrogenation of benzene. Compared with cyclohexane, the introduction of the alkene functional group makes cyclohexene more active and can be oxidized with better selectivity. Therefore, the oxidation reaction of cyclohexene is the key step for the synthesis of nylon-66 series products and their intermediates. In recent years, selenium catalysis technology has developed rapidly. Compared with metal catalysis, selenium is easily metabolized and ecologically safe, and its catalytic oxidation process usually uses hydrogen peroxide and molecular oxygen as clean oxidants, which are environmentally friendly. The selenium-catalyzed oxidation technology of cyclohexene is expected to be applied in the synthesis of nylon intermediates. The relevant progresses including both homogeneous and heterogeneous catalysis are reviewed, the principle from a scientific perspective is expounded and prospects for its industrial application are provided.

Key words: selenium, catalysis, oxidation, cyclohexene, nylon