Sodium Bicarbonate → HCID 66789617, compound

Participants

Reaction Steps

To a solution of N-[4-(4-methoxyphenyl)-2,2-dimethyl-3-oxo-3,4-dihydro-2H -1,4-benzoxazin-7-yl]methanesulfonamide (compound obtained in Example 14, 40 mg) in dichloromethane (5 mL) was added dropwise boron tribromide-dichloromethane solution (1.0 M, 0.32 mL) under cooling in dry ice-acetone bath. The reaction mixture was stirred at room temperature for 5.5 hours, and thereto was added an aqueous saturated sodium hydrogencarbonate solution. The mixture was extracted with chloroform and the organic layer was washed with brine, dried over sodium sulfate and concentrated in vacuo. The resultant residue was purified by column chromatography on silica gel (solvent; n-hexane/ethyl acetate=4/1→3/7) to give N-[4-(4-hydroxyphenyl)-2,2-dimethyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-7-yl]methanesulfonamide (35 mg) as a colorless powder.

Provenance & Evidence