反应 #2200595

反应方程式

methyl 4-amino-3,6-dichloro-5-fluoropyridine-2-carboxylate

tributyl(vinyl)tin

cesium fluoride

→

methyl 4-amino-3-chloro-5-fluoro-6-vinylpyridine-2-carboxylate

收率 67.3%

溶剂

dimethylformamide

反应条件

后处理

1. 1
   温度After cooling
2. 2
   浓缩the mixture was concentrated
3. 3
   过滤filtered through a silica gel plug
4. 4
   其他The solvents were removed
5. 5
   其他the crude product was purified by column chromatography (50% ethyl acetate in hexane)

实验过程

A solution of methyl 4-amino-3,6-dichloro-5-fluoropyridine-2-carboxylate (8.00 g, 33.0 mmol), tributyl(vinyl)tin (13.27 g, 42.0 mmol) and cesium fluoride (11.19 g, 73.6 mmol) in dimethylformamide (250 mL) was sparged with nitrogen for 15 minutes. Dichlorobis(triphenylphosphine)palladium (II) (1.17 g, 1.6 mmol) was then added and the mixture was heated at 90° C. overnight. After cooling, the mixture was concentrated, taken up into ethyl acetate and filtered through a silica gel plug. The solvents were removed and the crude product was purified by column chromatography (50% ethyl acetate in hexane) to give methyl 4-amino-3-chloro-5-fluoro-6-vinylpyridine-2-carboxylate (5.13 g, 22.2 mmol), mp 68-71° C.

来源