Ammonium Chloride → N-(4-chloro-3-methyl-1,2-oxazol-5-yl)-2-formylthiophene-3-sulfonamide

Temperature

0 °C

To a mixture of 3-[(4-chloro-3-methyl-1,2-oxazol-5-yl)sulfamoyl]-N-methoxy-N-methylthiophene-2-carboxamide described in Production Example 1-2 (8.0 g, 22 mmol) and tetrahydrofuran (160 mL), was added dropwise diisobutyl aluminum hydride (46 mL, 48 mmol, 1.0 M n-hexane solution) at −78° C., followed by stirring at 0° C. for 30 minutes. A saturated aqueous solution of ammonium chloride was added dropwise at 0° C. to the reaction mixture, which was then gradually allowed to warm to room temperature and stirred for 1 hour at that temperature. The reaction mixture was filtered with Celite, and water was added to the filtrate, which was then extracted with ethyl acetate. The organic layer was washed with brine, and the solvent was distilled away under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:methanol=30:1) to give the title compound (5.1 g, 75% yield).

1. temperatureto warm to room temperature
2. stirringstirred for 1 hour at that temperature
3. filtrationThe reaction mixture was filtered with Celite, and water
4. additionwas added to the filtrate, which
5. extractionwas then extracted with ethyl acetate
6. washThe organic layer was washed with brine
7. distillationthe solvent was distilled away under reduced pressure
8. customThe residue was purified by silica gel column chromatography (ethyl acetate:methanol=30:1)

ORD record

ord-79e40617f1124fd1baccd22a96b9cf06

Source dataset

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08592470B2