反応 #2348109

反応方程式

Intermediate 3

2-(4-bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

2-(4-Bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

2-(4-bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

BBr3

Intermediate 3

2-(4-bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

dichloromethane

2-(4-bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

→

desired product

収率 81.0%

2-(4-bromo-5-chloro-2-hydroxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one

収率 81.0%

溶媒

dichloromethane

反応条件

後処理

1. 1
   workup.ADDITIONAfter the addition
2. 2
   温度the reaction was warmed to room temperature
3. 3
   その他The reaction was quenched by the addition of 5-10 mL water
4. 4
   その他Volatile solvent was removed under vacuum
5. 5
   ろ過the crude product was filtered
6. 6
   洗浄washed with water
7. 7
   温度The solid was refluxed in a mixture of acetone and ethanol for 15 minutes
8. 8
   温度After cooling to room temperature
9. 9
   ろ過the purified product was filtered
10. 10
    洗浄washed with acetone and ethanol
11. 11
    その他The solid was dried under high vacuum

実験手順

2-(4-Bromo-5-chloro-2-methoxyphenyl)-2,4-dihydro-5-(5-bromothien-2-yl)-3H-1,2,4-triazol-3-one (Intermediate 3) (1.395 g) was suspended in anhydrous dichloromethane (20-25 mL/mmol of Intermediate 3) under argon and cooled to −78° C. A 1 M solution of BBr3 (9 mL) in anhydrous dichloromethane was added via a dropping funnel over a 45 minute period. After the addition was complete, the reaction was warmed to room temperature and stirred for 5 hours. The reaction was quenched by the addition of 5-10 mL water. Volatile solvent was removed under vacuum and the crude product was filtered and washed with water. The solid was refluxed in a mixture of acetone and ethanol for 15 minutes. After cooling to room temperature, the purified product was filtered and washed with acetone and ethanol. The solid was dried under high vacuum to yield 1.1 g (81%) of the desired product, Compound II.

出典