ε-Caprolactone is traditionally produced through Baeyer-Villiger oxidation of cyclohexanone oxidized by peracids in industry,which inevitably results in large discard acid and environmental pollution.To this end,a gr...ε-Caprolactone is traditionally produced through Baeyer-Villiger oxidation of cyclohexanone oxidized by peracids in industry,which inevitably results in large discard acid and environmental pollution.To this end,a green route toε-caprolactone was developed by coupling the direct generation of hydrogen peroxide from aerobic oxidation of benzhydrol catalyzed by NHPI and Baeyer-Villiger oxidation of cyclohexanone with the in situ hydrogen peroxide over Sn-Beta zeolites in one pot.Molecular oxygen was employed as the terminal oxidant,and the effects of several reaction factors were studied.Compared with one-step process,the one-pot two-step method noticeably improved the selectivity ofε-caprolactone.When the amount of in situ hydrogen peroxide was 0.72 equivalent,the selectivity ofε-caprolactone was obtained 94.8%with 39.2%conversion of cyclohexanone,and the efficiency of H_(2)O_(2) was up to 51.5%.As compared to the commercial 30 wt%aqueous H_(2)O_(2) added directly,in situ H_(2)O_(2) dramatically improved the selectivity ofε-caprolactone and had higher efficiency.Additionally,the catalyst could be easily separated from the reaction solution and reused several times without the remarkable loss of activity.展开更多
基金supported by the National Natural Science Foundation of China(No.22073081)the Fundamental Research Funds for the Central Universities.
文摘ε-Caprolactone is traditionally produced through Baeyer-Villiger oxidation of cyclohexanone oxidized by peracids in industry,which inevitably results in large discard acid and environmental pollution.To this end,a green route toε-caprolactone was developed by coupling the direct generation of hydrogen peroxide from aerobic oxidation of benzhydrol catalyzed by NHPI and Baeyer-Villiger oxidation of cyclohexanone with the in situ hydrogen peroxide over Sn-Beta zeolites in one pot.Molecular oxygen was employed as the terminal oxidant,and the effects of several reaction factors were studied.Compared with one-step process,the one-pot two-step method noticeably improved the selectivity ofε-caprolactone.When the amount of in situ hydrogen peroxide was 0.72 equivalent,the selectivity ofε-caprolactone was obtained 94.8%with 39.2%conversion of cyclohexanone,and the efficiency of H_(2)O_(2) was up to 51.5%.As compared to the commercial 30 wt%aqueous H_(2)O_(2) added directly,in situ H_(2)O_(2) dramatically improved the selectivity ofε-caprolactone and had higher efficiency.Additionally,the catalyst could be easily separated from the reaction solution and reused several times without the remarkable loss of activity.
