反応 #1909

反応方程式

product

3-cyano-4-trifluoromethylsulfenyl-5-(N-trifluoroacetylamino)pyrazole

ammonium hydroxide

hydrochloric acid

→

title compound

収率 87.6%

3-cyano-4-trifluoromethylsulfenyl-5-aminopyrazole

収率 87.6%

溶媒

methanol

ethyl acetate

反応条件

後処理

1. 1
   温度the solution was refluxed for 3 hours
2. 2
   洗浄The organic layer was washed several times with water and brine
3. 3
   乾燥dried over MgSO4
4. 4
   濃縮concentrated to dryness
5. 5
   その他to give an oily brown residue which
6. 6
   その他was recrystallized from methyl tert-butyl ether

実験手順

The product of Step E (55 g, 181 mmoles) was dissolved in methanol. 100 ml of ammonium hydroxide were added, the solution was refluxed for 3 hours and then stirred at room temperature for 15 hours. The methanolic solution was brought to pH7 using concentrated aqueous hydrochloric acid and diluted with ethyl acetate. The organic layer was washed several times with water and brine, dried over MgSO4 and concentrated to dryness to give an oily brown residue which was recrystallized from methyl tert-butyl ether to afford 33 g of the title compound, m.p. around 187° C.

出典