Hydrochloric Acid → HCID 21270174, compound

HRID 1194478Notes

Reaction equation

HRID 1194478 reaction equation
[OH:1][C:2]1[C:3]([OH:20])=[CH:4][C:5]2[O:10][CH:9]=[C:8]([C:11]3[CH:16]=[CH:15][C:14]([NH2:17])=[CH:13][CH:12]=3)[C:7](=[O:18])[C:6]=2[CH:19]=1.[C:21]1([S:27](Cl)(=[O:29])=[O:28])[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1.[OH-].[Na+].Cl>CN(C)C=O.O>[OH:1][C:2]1[C:3]([OH:20])=[CH:4][C:5]2[O:10][CH:9]=[C:8]([C:11]3[CH:12]=[CH:13][C:14]([NH:17][S:27]([C:21]4[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=4)(=[O:29])=[O:28])=[CH:15][CH:16]=3)[C:7](=[O:18])[C:6]=2[CH:19]=1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 7369Benzenesulfonyl chloride2×HCID 14798Sodium Hydroxide2×HCID 21270170HCID 21270170, compound

Product 1

HCID 21270174HCID 21270174, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

6,7-Dihydroxy-3-(4-aminophenyl)-4H-1-benzopyran-4-one [see Example 51a] (538 mg) is dissolved in a mixture of dimethylformamide and water 15:85 (5 ml) and the solution is heated to 90° in the presence of benzenesulfonyl chloride (210 mg). After 15 minutes the pH has dropped to 3 and it is adjusted to 9 by addition of a 25% sodium hydroxide solution. Benzenesulfonyl chloride (additional 143 mg) and 25% sodium hydroxide solution (total amount used: 1 ml) are added in the same way until the pH does not vary any more. Aqueous hydrochloric acid is then added to lower the pH to 3 and the solution is cooled until precipitation occurs. The precipitate is filtered, washed with water and dried to give 6,7-dihydroxy-3-(4-phenylsulfonylaminophenyl)-4H-1-benzopyran-4-one, m.p. 285°-286°.

Workup

  1. additionAfter 15 minutes the pH has dropped to 3 and it
  2. temperaturethe solution is cooled until precipitation
  3. filtrationThe precipitate is filtered
  4. washwashed with water
  5. customdried

Sources & evidence

ORD record
ord-44da808b4970461d91555f7972a9b78e
Source dataset
uspto-grants-1989_03
Patent number
US04814346

Reaction notes

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