反応 #1893

反応方程式

2-amino-5-chloro-2'-methoxybenzophenone

sodium bicarbonate

→

2-amino-5-chloro-2'-hydroxybenzophenone

収率 93.4%

溶媒

hydrogen bromide

反応条件

後処理

1. 1
   温度was heated for 1 hour
2. 2
   温度under reflux
3. 3
   抽出subjected to extraction with 100 ml of ethyl acetate
4. 4
   洗浄The extract solution was washed with water
5. 5
   乾燥dried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONthe solvent was then distilled off under reduced pressure
7. 7
   その他The residue was purified by means of silica gel column chromatography (eluent, hexane:ethyl acetate=10:1)

実験手順

A mixture of 2.15 g of 2-amino-5-chloro-2'-methoxybenzophenone and 20 ml of 47% hydrogen bromide was heated for 1 hour under reflux. The solution was rendered neutral with sodium bicarbonate, and subjected to extraction with 100 ml of ethyl acetate. The extract solution was washed with water and dried over anhydrous magnesium sulfate; the solvent was then distilled off under reduced pressure. The residue was purified by means of silica gel column chromatography (eluent, hexane:ethyl acetate=10:1) to yield 1.9 g of 2-amino-5-chloro-2'-hydroxybenzophenone as needles, m.p. 51° to 52° C.

出典