Methanol → HCID 18617288, compound

HRID 1263665Notes

Reaction equation

HRID 1263665 reaction equation
[NH2:1][C:2]1[O:6][N:5]=[C:4]([CH3:7])[C:3]=1[Br:8].[H-].[Na+].[C:11]1([S:17](Cl)(=[O:19])=[O:18])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.CO>C1COCC1.O>[Br:8][C:3]1[C:4]([CH3:7])=[N:5][O:6][C:2]=1[NH:1][S:17]([C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)(=[O:19])=[O:18]

Participants

7

Conditions

Temperature
2.5 °C

Procedure

A solution of 5-amino-4-bromo-3-methylisoxazole (354 mg, 2.0 mmol) in dry THF (1 ml) was added to a suspension of sodium hydride (60% dispersion in mineral oil, 188 mg, 4.4 mmol) in dry THF (1 ml) at 0° C. After stirring at 0-5° C. for 10 min., the reaction was warmed to room temperature for 10 min. to complete the reaction. The reaction mixture was re-cooled to 0° C. and benzenesulfonyl chloride (0.283 ml, 2.2 mmol) was added slowly. Stirring was continued for 20 min. at 0-5° C. Excess sodium hydride was decomposed by the addition of methanol (0.4 ml) followed by water (0.5 ml). The solvent was removed under reduced pressure. The residue was dissolved in water (20 ml), basified to pH 8-9 by the addition of sodium hydroxide and extracted with ethyl acetate (2×10 ml) to remove the neutral impurities. The aqueous layer was acidified with concentrate HCI (pH 2-3) and extracted with ethyl acetate (3×10 ml) The combined organic layer was dried over magnesium sulfate and concentrated under reduced pressure to give N-(4-bromo-3-methyl-5-isoxazolyl)benzenesulfonamide. The pure material was obtained by recrystallization using hexanes/ethyl acetate (0.59 g, 93% yield), m.p. 142-144° C.

Workup

  1. temperaturethe reaction was warmed to room temperature for 10 min.
  2. customthe reaction
  3. temperatureThe reaction mixture was re-cooled to 0° C.
  4. stirringStirring
  5. waitwas continued for 20 min. at 0-5° C
  6. customThe solvent was removed under reduced pressure
  7. dissolutionThe residue was dissolved in water (20 ml)
  8. additionbasified to pH 8-9 by the addition of sodium hydroxide
  9. extractionextracted with ethyl acetate (2×10 ml)
  10. customto remove the neutral impurities
  11. concentrationwith concentrate HCI (pH 2-3)
  12. extractionextracted with ethyl acetate (3×10 ml) The combined organic layer
  13. dry with materialwas dried over magnesium sulfate
  14. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-ae7d31a11f784c8098726135b89aaa1a
Source dataset
uspto-grants-2003_04
Patent number
US06541498B2

Reaction notes

Loading…