反応 #70953

反応方程式

5-(3,4-bis(benzyloxy)-5-nitrophenyl)-3-(2-(trifluoromethyl)pyridin-3-yl)-1,2,4-oxadiazole

boron tribromide

→

3-nitro-5-(3-(2-(trifluoromethyl)pyridin-3-yl)-1,2,4-oxadiazol-5-yl)benzene-1,2-diol

溶媒

dichloromethane

反応条件

後処理

1. 1
   workup.STIRRINGto stir at room temperature for one hour
2. 2
   その他The mixture was quenched by the careful addition of methanol
3. 3
   workup.STIRRINGAfter stirring at room temperature for thirty minutes
4. 4
   その他the volatiles were evaporated
5. 5
   workup.STIRRINGthe residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes
6. 6
   ろ過The resulting solid was filtered off
7. 7
   洗浄washed with water (25 mL)

実験手順

A solution of 5-(3,4-bis(benzyloxy)-5-nitrophenyl)-3-(2-(trifluoromethyl)pyridin-3-yl)-1,2,4-oxadiazole (0.099 g, 0.18 mmol) in dichloromethane (5 mL) was cooled to −78° C. with stirring under argon and treated with boron tribromide (0.18 g, 0.74 mmol) dropwise. The resulting deep purple suspension was then allowed to stir at room temperature for one hour before cooling again to −78° C. The mixture was quenched by the careful addition of methanol. After stirring at room temperature for thirty minutes, the volatiles were evaporated and the residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes. The resulting solid was filtered off, washed with water (25 mL) and then cold isopropanol (5 mL) to give 3-nitro-5-(3-(2-(trifluoromethyl)pyridin-3-yl)-1,2,4-oxadiazol-5-yl)benzene-1,2-diol as a yellow solid, 0.058 g (88%).

出典