Reaktion #5975

Reaktionsgleichung

methyl 2-methoxy-4-acetylamino-5-chlorobenzoate

BBr3

sodium hydroxide

→

4-acetylamino-5-chlorosalicylic acid

Lösungsmittel

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISSOLUTIONis dissolved
2. 2
   SonstigeThe two layers are separated
3. 3
   Filtrationfiltered
4. 4
   Waschenwashed with water
5. 5
   Sonstigeevaporated to dryness

Vorschrift

To a mixture of 16 g of methyl 2-methoxy-4-acetylamino-5-chlorobenzoate in 130 ml of methylene chloride is slowly added 100 ml of a methylene chloride solution of borontribromide (250 g BBr3 per liter) and stirring continued for 24 hours. 1N sodium hydroxide solution is then added until all material is dissolved. The two layers are separated and the aqueous layer is acidified with 1N hydrochloric acid, filtered, washed with water and evaporated to dryness to give 4-acetylamino-5-chlorosalicylic acid which is used directly in the next step.

Quelle