Methanol → HCID 18617288, compound

HRID 439347Notes

Reaction equation

HRID 439347 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

Reactant 4

HCID 887MethanolHCID 7369Benzenesulfonyl chlorideHCID 24758Sodium hydride2×HCID 104875194-Bromo-3-methylisoxazol-5-amine

Product 1

HCID 18617288HCID 18617288, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×

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

Sources & evidence

ORD record
ord-219a45c504944839bf1c822b63adac9c
Source dataset
uspto-grants-1996_05
Patent number
US05514691

Reaction notes

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