利用1-(3-磺酸基)丙基-4-甲基吡啶与磷钨酸、磷钼酸和硅钨酸反应获得3种不同的4-甲基吡啶类杂多酸盐,考查了其催化合成尼泊金酯的催化性能.实验表明,3种4-甲基吡啶类杂多酸盐都具有反应控制相转移的优点,其中4-甲基吡啶磷钨酸盐的反应控制相转移能力最佳.当反应条件为 n(醇): n(酸): n(催化剂)=3:1:0.03,反应时间为8 h,反应温度为120℃时,1-(3-磺酸基)丙基-4-甲基吡啶磷钨杂多酸盐催化合成尼泊金乙酯的产率可达到87.7%% Three different salts of 4-methyl pyridine heteropoly acid were synthesized by 1-(3-sulfonic acid group) propyl-4-methyl pyridine reacting with phosphotungstic acid, phosphomolybdic acid and silicotungstic acid. Their catalytic performance was studied by synthetic reaction of the nipagin ethyl esters. The experiments showed that three types of salts of 4-methyl pyridine heteropoly acid all have the ability of reaction-controlled phase-transfer and that 1-(3-sulfonic acid group) propyl-4-methyl pyridine phosphotungstate has the best phase-transfer perfor⁃mance. When using 1-(3-sulfonic acid group) propyl-4-methyl pyridine phosphotungstate as catalyst, n(acid):n(al⁃cohol): n(catalyst)=3:1:0.03, reaction time for 8h, reaction temperature at 120 ℃ , the yield of nipagin ethyl ester can be achieved to 87.7%.
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