反应 #44199

反应方程式

Cyanogen bromide

4-(4-bromo-2-fluorophenylamino)-5-fluoro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid hydrazide

cyanogen bromide

NaHCO3

→

desired product

收率 89.2%

5-(5-amino-[1,3,4]oxadiazol-2-yl)-4-(4-bromo-2-fluorophenylamino)-3-fluoro-1-methyl-1H-pyridin-2-one

收率 89.2%

溶剂

water

dioxane

反应条件

后处理

1. 1
   workup.WAITAfter 19 hours
2. 2
   萃取extracted with ethyl acetate
3. 3
   洗涤The combined organic extracts were washed with brine
4. 4
   干燥dried (MgSO4)
5. 5
   浓缩concentrated under reduced pressure
6. 6
   其他Crystallization (MeOH:THF)

实验过程

Cyanogen bromide (36 mg, 0.31 mmol) was added to a suspension of 4-(4-bromo-2-fluorophenylamino)-5-fluoro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid hydrazide (63 mg, 0.169 mmol) in dioxane (2 mL) followed by an aqueous NaHCO3 (2 mL of a 0.09 M solution) solution. After 17 hours, additional cyanogen bromide (14 mg) was added. After 19 hours, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic extracts were washed with brine, dried (MgSO4) and concentrated under reduced pressure. Crystallization (MeOH:THF) followed by trituration (Et2O:MeOH 5:1) gave clean desired product as a white solid (60 mg, 89%). MS APCI (+) m/z 398, 400 (M+, Br pattern) detected; 1H NMR (400 MHz, CD3OD) δ 8.06 (s, 1H), 7.37 (d, 1H), 7.31 (d, 1H), 7.10 (td, 1H), 3.64 (s, 3H).

来源