Toluene → Ethyl 2-chloro-5-sulfamoylthiophene-3-carboxylate

HRID 1197427Notes

Reaction equation

HRID 1197427 reaction equation
[Cl:1][C:2]1[S:6][C:5]([S:7]([NH2:10])(=[O:9])=[O:8])=[CH:4][C:3]=1[C:11]([OH:13])=[O:12].[C:14]1(C)C=CC=C[CH:15]=1>OS(O)(=O)=O.C(O)C>[Cl:1][C:2]1[S:6][C:5]([S:7]([NH2:10])(=[O:9])=[O:8])=[CH:4][C:3]=1[C:11]([O:13][CH2:14][CH3:15])=[O:12]

Participants

5

Reactant 2

HCID 1140TolueneHCID 12014982-Chloro-5-sulfamoylthiophene-3-carboxylic acid

Product 1

HCID 19106450Ethyl 2-chloro-5-sulfamoylthiophene-3-carboxylate

Reagents, catalysts & solvents 2

HCID 1118Sulfuric AcidCatalystHCID 702EthanolSolvent

Procedure

To a round bottom flask were added 5-chloro-4-carboxythiophene-2-sulfonamide (5.0 g, 20.7 mmole) along with toluene (25 mL), ethanol (20 ml), and conc. H2SO4 (25 drops). The reaction mixture was refluxed for 96 hours. The reaction mixture was cooled and the solvent was removed under vacuum. The residue was then poured onto ice and the pH adjusted to ~8.0 using 10% sodium carbonate. The basic aqueous layer was extracted with ethyl acetate and the organic layer was washed with water, brine, and dried (MgSO4). Solvent removal yielded 3.92 g (70%) of an off white solid which was used as is: mp =98°-99° C.

Workup

  1. temperatureThe reaction mixture was refluxed for 96 hours
  2. temperatureThe reaction mixture was cooled
  3. customthe solvent was removed under vacuum
  4. additionThe residue was then poured onto ice
  5. extractionThe basic aqueous layer was extracted with ethyl acetate
  6. washthe organic layer was washed with water, brine
  7. dry with materialdried (MgSO4)
  8. customSolvent removal
  9. customyielded 3.92 g (70%) of an off white solid which
  10. custommp =98°-99° C.

Sources & evidence

ORD record
ord-8077273d383c4c3991829319258dbb7d
Source dataset
uspto-grants-1994_01
Patent number
US05276025

Reaction notes

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