반응 #2254182

반응 방정식

Acetyl chloride

AlCl3

2-bromo-3-methylthiophene

→

1-(5-bromo-4-methyl-thiophen-2-yl)-ethanone

수율 56.6%

용매

dichloromethane

반응 조건

후처리

1. 1
   workup.WAITAfter 1 hour at 0° C.
2. 2
   기타the reaction is quenched
3. 3
   workup.ADDITIONby added water (100 ml)
4. 4
   추출The mixture is extracted three times with dichloromethane
5. 5
   건조dried over MgSO4
6. 6
   농축concentrated in vacuo
7. 7
   기타The crude product is purified by chromatography on silica gel (180 g)
8. 8
   세척eluting with a mixture of ethyl acetate and heptane (1:6)

실험 절차

Acetyl chloride (7.09 g) is added to a suspension of AlCl3 (11.53 g) in dichloromethane (310 ml) at 0° C. After 45 minutes at 0° C., 2-bromo-3-methylthiophene (5.0 g) is added dropwise. After 1 hour at 0° C., the reaction is quenched by added water (100 ml). The mixture is extracted three times with dichloromethane. The organic phases are combined, dried over MgSO4 and concentrated in vacuo. The crude product is purified by chromatography on silica gel (180 g) eluting with a mixture of ethyl acetate and heptane (1:6) to yield 1-(5-bromo-4-methyl-thiophen-2-yl)-ethanone (3.5 g) as a brown solid.

출처