Reaktion #321594

Reaktionsgleichung

Carbonyldiimidazole

piperonylic acid

N-(4-bromo-3-methyl-5-isoxazolyl)-2-aminocarbonylthiophene-3-sulfonamide

N-(4-bromo-3-methyl-5-isoxazolyl)-2-(aminocarbonyl)thiophene-3-sulfonamide

NaH

→

N-(4-bromo-3-methyl-5-isoxazolyl)-2-{[(3,4-methylenedioxy)benzoyl]aminocarbonyl}thiophene-3-sulfonamide

Ausbeute 3.6%

Lösungsmittel

Water

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe mixture was stirred at room temperature for 8 hours
2. 2
   Sonstigeto destroy the excess NaH
3. 3
   SonstigeThe solvent was then evaporated
4. 4
   Sonstigethe residue was partitioned between 1N HCl and EtOAc
5. 5
   TrocknenThe organic layer was dried (MgSO4)
6. 6
   Filtrationthe solid filtered
7. 7
   Einengenthe filtrate concentrated
8. 8
   SonstigeThe residue was recrystalized from EtOAc

Vorschrift

Carbonyldiimidazole (21 3 mg. 1.31 mmol) was added to a solution of piperonylic acid (181.5 mg., 1.09 mmol) in dry THF (10 ml). The resulting mixture was stirred for 15 minutes. N-(4-bromo-3-methyl-5-isoxazolyl)-2-aminocarbonylthiophene-3-sulfonamide (Example 89) (400 mg, 1.09 mmol) and NaH (175 mg, 60% in mineral oil, 4.37 mmol) were added sequentially. The mixture was stirred at room temperature for 8 hours. Water was added to destroy the excess NaH. The solvent was then evaporated and the residue was partitioned between 1N HCl and EtOAc. The organic layer was dried (MgSO4), the solid filtered and the filtrate concentrated. The residue was recrystalized from EtOAc to give N-(4-bromo-3-methyl-5-isoxazolyl)-2-{[(3,4-methylenedioxy)benzoyl]aminocarbonyl}thiophene-3-sulfonamide (20 mg, 3.6% yield) as a yellowish powder (m.p. 90°-93° C.).

Quelle