In this paper, it was found that isopropylidene (1-hydroxy-3-oxo-butylidene) malonate 4 was a heat unstable compound and the one step convenient methods for preparation of 4-hydroxy-6-methyl-2-pyrone 1 and 3-carboxy-4...In this paper, it was found that isopropylidene (1-hydroxy-3-oxo-butylidene) malonate 4 was a heat unstable compound and the one step convenient methods for preparation of 4-hydroxy-6-methyl-2-pyrone 1 and 3-carboxy-4-hydroxy-6-methyl-2-pyrone 2 in good yields were reported. Isopropylidene malonate 3、diketen and triethylamine reacted in chloroform to give 2, and in the mixture of dichloromethane and chlorobenzene to offer 1.展开更多
通过水代替有机溶剂来提纯2-丙基-4,5-1 H-咪唑二羧酸二乙酯和4-(1-羟基-1-甲基乙基)-2-丙基-1 H-咪唑-5-羧酸乙酯的新方法,使得改进工艺更加绿色简便。采用1 H NMR、13 C NMR、IR、MS谱图对反应后的产品和未知杂质进行结构鉴定,确证为...通过水代替有机溶剂来提纯2-丙基-4,5-1 H-咪唑二羧酸二乙酯和4-(1-羟基-1-甲基乙基)-2-丙基-1 H-咪唑-5-羧酸乙酯的新方法,使得改进工艺更加绿色简便。采用1 H NMR、13 C NMR、IR、MS谱图对反应后的产品和未知杂质进行结构鉴定,确证为一水合4-(1-羟基-1-甲基乙基)-2-丙基-1 H-咪唑-5-羧酸乙酯和4-乙酰基-2-丙基-1 H-咪唑-5-羧酸乙酯。对反应的可能机理进行初步研究。展开更多
文摘In this paper, it was found that isopropylidene (1-hydroxy-3-oxo-butylidene) malonate 4 was a heat unstable compound and the one step convenient methods for preparation of 4-hydroxy-6-methyl-2-pyrone 1 and 3-carboxy-4-hydroxy-6-methyl-2-pyrone 2 in good yields were reported. Isopropylidene malonate 3、diketen and triethylamine reacted in chloroform to give 2, and in the mixture of dichloromethane and chlorobenzene to offer 1.
文摘通过水代替有机溶剂来提纯2-丙基-4,5-1 H-咪唑二羧酸二乙酯和4-(1-羟基-1-甲基乙基)-2-丙基-1 H-咪唑-5-羧酸乙酯的新方法,使得改进工艺更加绿色简便。采用1 H NMR、13 C NMR、IR、MS谱图对反应后的产品和未知杂质进行结构鉴定,确证为一水合4-(1-羟基-1-甲基乙基)-2-丙基-1 H-咪唑-5-羧酸乙酯和4-乙酰基-2-丙基-1 H-咪唑-5-羧酸乙酯。对反应的可能机理进行初步研究。
