反应详情

A solution of triethylamine (0.260 mL, 1.85 mmol) and methyl 3-amino-2,6-difluorobenzoate (0.257 mL, 1.85 mmol) was added dropwise to sulfuryl dichloride (0.156 mL, 1.85 mmol) in DCM (3 mL) at −78° C. After 2 hours, N-methylethanamine (0.304 mL, 3.70 mmol) was added and then let warm to room temperature overnight. The solvent was concentrated under reduced pressure, and the residue was taken up in NaOH (2 mL, 1M) and washed with EtOAc. The aqueous pH was lowered to below 3 and, the mixture was extracted with EtOAc (3×5 mL). The combined organic layers were dried over sodium sulfate, decanted and concentrated under reduced pressure. The residue was purified via silica gel chromatography eluting with 7:3 hexane:EtOAc to afford impure methyl 3-(N-ethyl-N-methylsulfamoylamino)-2,6-difluorobenzoate (0.280 g, 49.0% yield).

1. concentrationThe solvent was concentrated under reduced pressure
2. washwashed with EtOAc
3. extractionthe mixture was extracted with EtOAc (3×5 mL)
4. dry with materialThe combined organic layers were dried over sodium sulfate
5. customdecanted
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified via silica gel chromatography
8. washeluting with 7:3 hexane