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为了得到高质量和高收率的3-甲氧基-4-羟基苯乙醇酸,使愈创木酚和乙醛酸在碱性水溶液中在固体酸催化剂存在下进行缩合反应,反应温度15℃,反应时间18h。将生成的3-甲氧基-4-羟基苯乙醇酸以钠盐形式沉淀分离出来,产品纯度98%。以γ-氧化铝、4A分子筛、活性二氧化硅、轻质氧化镁和活性氧化锌等两性氧化物用做催化剂进行研究。以4A分子筛作催化剂时收率达88·6%,比无催化剂时收率提高8·8%。
In order to obtain high quality and high yield of 3-methoxy-4-hydroxy mandelic acid, guaiacol and glyoxylic acid are subjected to a condensation reaction in an alkaline aqueous solution in the presence of a solid acid catalyst at a reaction temperature of 15 ° C. , Reaction time 18h. The resulting 3-methoxy-4-hydroxy mandelic acid was isolated as a sodium salt by precipitation and the product was purified to 98% purity. Ammonia such as γ-alumina, 4A molecular sieves, activated silica, light magnesia and active zinc oxide were used as catalysts. With 4A molecular sieve as catalyst, the yield was 88.6%, which was 8.8% higher than that without catalyst.