摘要
凉味剂N-乙基-L-薄荷基甲酰胺,凉感强度是薄荷醇的1.5倍,具有无气息、低挥发性、无苦味、无灼烧感、低毒性、凉感持久等优点。该文考察了以薄荷醇为起始原料,通过格氏反应制备N-乙基-L-薄荷基甲酰胺的方法。薄荷醇与五氯化磷在无水氯化铁的催化作用下反应得到氯代物,收率可达90%左右。薄荷基氯的格氏试剂与二氧化碳反应,干冰与二氧化碳气体相比较,二氧化碳气体反应得到薄荷基-3-羧酸的产率更高,格氏试剂与二氧化碳气体的摩尔比为1∶45,反应温度为-40℃,得到薄荷基3-羧酸的产率达55%。薄荷基-3-羧酸转化为酰氯后与乙胺反应得粗产物,GC分析表明,其中薄荷酰胺和新薄荷酰胺的摩尔比为87/13。粗产物经重结晶后得纯的N-乙基-L-薄荷基甲酰胺。总收率约40%。
The new cooling agent N-ethyl-L-menthane-3-carboxamide （ Ⅰ ） has cooling intensity 1.5 folds as strong as L-menthol. It possesses many advantages, such as weak odor, low volatility, no bitter taste,no burning sensation,low toxicity and long-lasting cooling sensation. Synthesis of Ⅰ started from L-menthol through the Grignard reaction. L-Menthol reacted with phosphorus pentachloride catalyzed by anhydrous ferric chloride to give the chlorinated product menthyl chloride （ Ⅱ ） in about 90% yield. Menthane-3-carboxylic acid（ Ⅲ ） was obtained in about 55% yield by reacting the Grignard reagent of Ⅱ with gaseous carbon dioxide at -40 ℃ with the Grignard reagent/carbon dioxide molar ratio of 1/ 45. Then Ⅲ was transformed to acid chloride, and reacted with ethyl amine to give the crude product, in which the menthane-3-carboxamide/neomenthane-3-carboxamide ratio was 87/13 by GC analysis. Reerystallization of the crude product gave pure Ⅰ. The overall yield was about 40%.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2008年第11期1097-1100,1113,共5页
Fine Chemicals
基金
浙江省“食品科学与工程”重中之重学科建设项目开放课题(ZSZKF200714)
北京市新世纪百千万人才工程培养经费资助项目~~
