【摘要】 为找到一种更加适合工业化生产的反应条件和重结晶条件,简化合成工艺,降低成本,用L-肉碱和乙酰氯为原料,冰乙酸为溶剂,不用催化剂直接酰化合成乙酰-L-肉碱,用异丙醇共沸蒸馏的方法除去减压蒸馏残存的冰乙酸.因此,在用异丙醇结晶时,减少了残存的冰乙酸对产物乙酰-L-肉碱的部分溶解,使收率从文献的78%提高到82%,并且对结晶条件进行详细考察.确定在慢搅拌、慢降温、降温至0℃的工艺条件下,结晶效果好、收率高.产物的结构经过红外光谱和核磁共振13C-NMR谱进行表征.更多还原

【Abstract】 The research consists of synthesis and recrystallization of acetyl L-carnitine to develop manufacture method on industrial scale.Acetyl-L-carnitine was prepared from L-carnitine and acetyl chloride with ice acetic acid as solvent,without any catalyst by direct acylation method.A few of ice acetate acid was removed by azeotropic distillation with isopropanol,the yield of acetyl-L-carnitine could reach 82 %,instead of 78 %.The effects of agitation and temperature on the crystallization were investigated.The results indicated that the temperature gradually reached 0 ℃ at gentle agitation.Its molecular structure was identified by IR and（）¹³C-NMR analysis.更多还原