杂环的酚羟基的卤代.doc

经典化学合成反应标准操作
杂环的酚羟基或醚的烷氧基卤代反应
目录
前言………………………………………………………………2
***代………………………………………………………………2
***氧磷***代反应示例……………………………2
***氧磷与五***化磷混合处理***代反应示例………3
***氧磷***代反应示例………………………3
溴代………………………………………………………………4
POBr3溴代反应示例(一)………………………4
POBr3溴代反应示例(二)……………………………4
***法溴代反应示例………………………5
………………………………5
参考文献…………………………………………………………6

杂环的酚羟基的通常较易被卤代,其也是杂环一种常见的官能团的转换方式之一,卤代反应常见的有***代、溴代反应。另外,在存在吸电子基的杂环上,不仅酚羟基容易被卤代,而且烷氧基(甲氧基,乙氧基等)也很容易被卤代。因此其也是合成的一种策略。经常有文献首先将杂环卤代物用甲氧基取代后,利用甲氧基推电子效应完成一系列转化后,再将甲氧基卤代回来。
2. ***代
杂环的酚羟基的***代一般用三***氧磷1,2,3或三***氧磷与五***化磷混合4,5处理。使用五***化磷的条件更强,用于难以发生的杂环的酚羟基的***代反应。杂环烷氧基的***代也可用三***氧磷直接处理6.
杂环的酚羟基的用三***氧磷***代反应示例1
2-Hydroxy-3-iodo-5-nitropyridine 1 ( g, mol) was added to quinoline (16 mL, mol). The reaction flask was cooled to 5 degree and phosphoryl chloride (25 mL, mol) was added dropwise. The mixture was blanketed with argon and heated to 120 degree for 2 h. plete consumption of the precursor, as indicated by TLC, the mixture was cooled to room temperature and 100 mL of H2O was added. The mixture was then cooled to 0 degree, and the resulting brown solid was filtered. Recrystallization from ethanol gave sand-color crystals 2 (60 g, , 78% yield).
杂环的酚羟基用三***氧磷与五***化磷混合处理***代反应示例5
To a solution of g of 1 in 16 mL of phosphorus oxychloride was heated to reflux and added