O-Protected 3-hydroxy-oxazolidin-2,4-diones: novel precursors in the synthesis of α-hydroxyhydroxamic acids
作者:Thomas Kurz、Khalid Widyan
DOI:10.1039/b404950k
日期:——
O-Protected 3-hydroxyoxazolidin-2,4-diones have been prepared in a novel one-pot reaction by subsequent treatment of cyanohydrins with 1,1â²-carbonyldiimidazole and O-protected hydroxylamines followed by acidic hydrolysis of the intermediate 4-imino-oxazolidin-2-ones. Decarbonylation of O-protected 3-hydroxyoxazolidin-2,4-diones by catalytic amounts of sodium methoxide, lithium hydroxide, sodium carbonate and caesium carbonate in methanol afforded O-protected α-hydroxyhydroxamic acids in excellent yields. Their deprotection provided a series of novel α-hydroxyhydroxamic acids.
O-保护的3-羟基氧杂啉-2,4-二酮通过一个新颖的一锅反应制备,方法是先将氰醇与1,1'-碳基二咪唑和O-保护的氢氧胺处理,然后对中间体4-亚氨基氧杂啉-2-酮进行酸性水解。用催化量的醇钠、氢氧化锂、碳酸钠和碳酸铯在甲醇中对O-保护的3-羟基氧杂啉-2,4-二酮进行脱羰基反应,得到了优良产率的O-保护的α-羟基羟肟酸。去保护后得到了一系列新型的α-羟基羟肟酸。