Baeyer-Villiger Oxidation of Cyclic Ketones Catalyzed by Amino Alcohol Heteropoly Acid Ionic Liquid

A series of amino alcohol heteropolyacid ionic liquids was synthesized and used to catalyze the Baeyer-Villiger oxidation of cycloketones. 2-Heptylcyclopentanone was used as a template substrate and H2O2 was used as an oxidant. The catalytic activity of such amino alcohol heteropoly acid ionic liquids was investigated. The catalyst with the highest catalytic activity was [Pro-ps] H2PW12O40. The obtained optimum reaction conditions were n(2-heptylcyclopentanone) n(catalyst) n(H2O2) = 1 0. 03 4 at 40 degrees C for 8 h by solvent free. Under the optimum conditions, the conversion rate of 2-heptylcyclopentanone was 98. 19%, and the selectivity of delta-dodelactone was up to 82. 84%. After simple treatment, the ionic liquid [Pro-ps] H2PW12O40 could be reused, and the catalytic activity did not decrease significantly after five cycles. [Pro-ps] H2PW12O40 could also be used to catalyze the Baeyer-Villiger oxidation of various cyclic ketones. The results showed that the catalyst had good reusability and substrate adaptability.