反応 #44199

反応方程式

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

収率 89.2%

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

収率 89.2%

溶媒

water

dioxane

反応条件

後処理

1. 1
   workup.WAITAfter 19 hours
2. 2
   抽出extracted with ethyl acetate
3. 3
   洗浄The combined organic extracts were washed with brine
4. 4
   乾燥dried (MgSO4)
5. 5
   濃縮concentrated under reduced pressure
6. 6
   その他Crystallization (MeOH:THF)

実験手順

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).

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