【摘要】 以高氯酸为催化剂,D-葡萄糖和L-鼠李糖分别与乙酸酐反应,制得相应的全乙酰化糖,不经分离直接加入乙酰溴和甲醇,利用反应生成的溴化氢原位发生溴代反应,一锅法制备了溴代乙酰葡萄糖和溴代乙酰鼠李糖,收率分别达到92.5%和85.6%。从产品结晶后的母液中,以干燥的二氯甲烷作溶剂,采用重结晶法分离得到溴代乙酰鼠李糖合成的副产物2,3,4-三-O-乙酰基鼠李糖。产品和副产物的结构均经过核磁共振氢谱、碳谱和高分辨质谱确认。更多还原

【Abstract】 A facile and efficient one-pot method for the preparation of acetobromoglucose or acetobromorhamnose was developed. Firstly,treatment of D-glucose or L-rhamnose with acetic anhydride led to the corresponding peracetylated intermediate in the presence of catalytic amount of perchloric acid,respectively. Then,a bromination of the peracetylated intermediate with hydrogen bromide occurred by directly adding acetyl bromide and methyl alcohol into the above reaction solution. The yields of acetobromoglucose and acetobromorhamnose were 92. 5% and 85. 6%,respectively. 2,3,4-Tri-O-acetyl-rhamnopyranose as a by-product was obtained by using dry dichloromethane to recrystallize the mother liquor of acetobromorhamnose. The prepared products and by-product were characterized by proton nuclear magnetic resonance spectroscopy(1HNMR),carbon nuclear magnetic resonance spectroscopy(13CNMR) and high resolution mass spectrometry(HRMS).更多还原