Reacción #1350593

Ecuación de reacción

3-amino-2-methylbenzoic acid

methyl isothiocyanate

bromine

→

2-Methylamino-4-methylbenzothiazole-5-carboxylic Acid

Disolventes

acetic acid

acetic acid

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturato cool
2. 2
   FiltraciónThe precipitate was filtered off
3. 3
   Concentraciónthe filtrate was concentrated to about 50 ml
4. 4
   workup.ADDITIONthe remaining filtrate and the precipitate were added to water
5. 5
   Filtraciónthe precipitate was filtered off at 8° C
6. 6
   LavadoIt was subsequently washed with water
7. 7
   Otrodried

Procedimiento

99 g of 3-amino-2-methylbenzoic acid (0.655 mol) were initially charged in 500 ml of acetic acid and, at 80° C,. admixed with 51 g of methyl isothiocyanate (7 mol) in 100 ml of acetic acid. After 2 h, 106 g of bromine (0.66 mol) in 20 ml of acetic acid were added dropwise at 50° C. The mixture was subsequently heated at about 100° C. for 2 h and, after the reaction had ended, allowed to cool. The precipitate was filtered off, the filtrate was concentrated to about 50 ml and the remaining filtrate and the precipitate were added to water. The aqueous phase was adjusted to pH 5 and the precipitate was filtered off at 8° C. It was subsequently washed with water and dried. Yield: 66 g (42%).

Fuente