Studies on catalytic synthesis of fructone by L-proline ionic liquid

The synthesis of fructone from ethyl acetoacetate and ethylene glycol using L-proline ionic liquid as catalyst was investigated.Various reaction parameters such as ratio of ethyl acetoacetate to ethylene glycol,catalyst amount,the catalyst dosage,the effects of the sort of water-carrying agent and the water-carrying reagent amount,reaction time,et al on the yield were investigated in details.The experimental results indicated that the molar ratio of ethyl acetoacetate to ethylene glycol was 1.0∶1.4,the quantity of catalyst was equal to 2.0 g/mol ethyl acetoacetate,amount of cyclohexane was 40 mL,and the reaction time was 3.5 h.The yield of fructone reached 88.9 % under the optimum condition.The isolation of the desired products could be achieved via simple separation and ionic liquids could be reused.The catalytic activity was not decreased obviously after 4 times recycle.