Catalytic Synthesis of Cyclohexanone D-isoascorbic Acid Ketal by Aluminum Trichloride

The effect of different catalysts on the synthesis of cyclohexanone D-isoascorbic acid ketal(3) were investigated.The results showed that aluminum trichloride(AlCl3) exhibited the best catalytic activity.The optimal reaction conditions at 120 ℃ for 2.5 h in DMAc(12 mL) using cyclohexane(10 mL) as water-carrying agent were as follows: cyclohexanone was 20 mmol;n(cyclohexanone) ∶ n(D-isoascorbic acid)was 1.0 ∶ 1.6;AlCl3 was 1 mmol.The yield of 3 was 86.48% under the optimal reaction conditions.