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

HRID 4902

Reaction equation

HRID 4902 reaction equation
[NH2:1][C:2]1[CH:11]=[CH:10][C:5]([C:6]([O:8][CH3:9])=[O:7])=[C:4]([S:12]([NH2:15])(=[O:14])=[O:13])[CH:3]=1.[CH3:16][C:17]1[C:18]([O:20][C:21](=O)[C:22]=1[CH3:23])=[O:19]>C(O)(=O)C>[NH2:15][S:12]([C:4]1[CH:3]=[C:2]([N:1]2[C:18](=[O:19])[C:17]([CH3:16])=[C:22]([CH3:23])[C:21]2=[O:20])[CH:11]=[CH:10][C:5]=1[C:6]([O:8][CH3:9])=[O:7])(=[O:13])=[O:14]

Participants

4

Reactant 2

HCID 13010Dimethylmaleic anhydrideHCID 10977277Methyl 4-amino-2-sulfamoylbenzoate

Product 1

HCID 14837212methyl 2-(aminosulfonyl)-4-(2,5-dihydro-3,4-dimethyl-2,5-dioxo-1H-pyrrol-1-yl)benzoateYield 43%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

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.

Workup

  1. distillationAcetic acid was then distilled off from the reaction mixture
  2. additionfollowed by the addition of 20 ml of ice water to the oily residue
  3. customAfter the mixture thus formed
  4. filtrationthe resulting precipitate was collected by filtration
  5. customdried in air

Sources & evidence

ORD record
ord-b9ac6e1cabe64925a2abe6ef104073ff
Source dataset
uspto-grants-1993_09
Patent number
US05242894

Linked notes

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