Reacción #4998

Ecuación de reacción

2,3-dimethylmaleic anhydride

methyl 4-amino-2-(aminosulfonyl)benzoate

→

methyl 2-(aminosulfonyl)-4-(2,5-dihydro-3,4-dimethyl-2,5-dioxo-1H-pyrrol-1-yl)benzoate

Rendimiento 43.0%

Disolventes

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.DISTILLATIONAcetic acid was then distilled off from the reaction mixture
2. 2
   workup.ADDITIONfollowed by the addition of 20 ml of ice water to the oily residue
3. 3
   OtroAfter the mixture thus formed
4. 4
   Filtraciónthe resulting precipitate was collected by filtration
5. 5
   Otrodried in air

Procedimiento

In 3 ml of acetic acid, 1 mmol of methyl 4-amino-2-(aminosulfonyl)benzoate and 1.05 mmol of 2,3-dimethylmaleic anhydride were stirred at 80° C. for 40 hours. Acetic acid was then distilled off from the reaction mixture, followed by the addition of 20 ml of ice water to the oily residue. After the mixture thus formed was stirred for 2 hours, the resulting precipitate was collected by filtration and then dried in air. Yield: 43%. Its physicochemical properties are shown in Table 8.

Fuente