Reacción #1893

Ecuación de reacción

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

sodium bicarbonate

→

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

Rendimiento 93.4%

Disolventes

hydrogen bromide

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawas heated for 1 hour
2. 2
   Temperaturaunder reflux
3. 3
   Extracciónsubjected to extraction with 100 ml of ethyl acetate
4. 4
   LavadoThe extract solution was washed with water
5. 5
   Secadodried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONthe solvent was then distilled off under reduced pressure
7. 7
   OtroThe residue was purified by means of silica gel column chromatography (eluent, hexane:ethyl acetate=10:1)

Procedimiento

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.

Fuente