反応 #172393

反応方程式

2-fluoro-5-nitrotoluene

N-bromosuccinimide

azodiisobutyronitrile

→

2-(Bromomethyl)-1-fluoro-4-nitrobenzene

溶媒

carbon tetrachloride

反応条件

後処理

1. 1
   温度the mixture is heated
2. 2
   温度under reflux
3. 3
   温度to cool
4. 4
   ろ過filtered
5. 5
   その他evaporated to dryness under reduced pressure
6. 6
   workup.DISSOLUTIONThe residue is dissolved in 300 ml of dichloromethane
7. 7
   workup.ADDITION300 g of sea sand are added
8. 8
   濃縮Once more, the mixture is then concentrated to dryness under reduced pressure
9. 9
   その他The product is chromatographed
10. 10
    workup.ADDITIONa 20:1 mixture of cyclohexane and ethyl acetate
11. 11
    その他the product fractions are evaporated to dryness under reduced pressure
12. 12
    その他The residue is crystallized with cyclohexane
13. 13
    その他dried under reduced pressure

実験手順

186 g (1.20 mol) of 2-fluoro-5-nitrotoluene are dissolved in 1.2 l of carbon tetrachloride, and 214 g (1.20 mol) of N-bromosuccinimide are added. 19.7 g (120 mmol) of azodiisobutyronitrile are added, and the mixture is heated under reflux. After 16 h, the mixture is allowed to cool, filtered and evaporated to dryness under reduced pressure. The residue is dissolved in 300 ml of dichloromethane, and 300 g of sea sand are added. Once more, the mixture is then concentrated to dryness under reduced pressure, and the residue is applied to a 1 kg silica gel column. The product is chromatographed using a 20:1 mixture of cyclohexane and ethyl acetate, and the product fractions are evaporated to dryness under reduced pressure. The residue is crystallized with cyclohexane and dried under reduced pressure. This gives 92 g (32% of theory) of the desired product.

出典