Hydrochloric Acid → HCID 14722417, compound

Participants

Reaction Steps

3.92 g of 2-hydroxy-7-methylsulfonylamino-3-nitro-6-phenoxy-4H-1-benzopyran-4-one was mixed with 80 ml of a 1N aqueous sodium hydroxide solution. The mixture was stirred for 5 hours at 20°-25° C. The mixture was adjusted to pH 5 with 4N hydrochloric acid. 50 ml of ethyl acetate was added thereto. The organic layer was separated, washed with water and a saturated aqueous sodium chloride solution in this order, and dried with anhydrous magnesium sulfate. The solvent was removed by distillation under reduced pressure. The resulting yellow solid was dissolved in N,N-dimethylformamide. 2.62 g of N,N-dimethylformamide dimethylacetal was added thereto. The mixture was stirred for 1 hour at 20°-25° C. The reaction mixture was introduced into 300 ml of water. The resulting mixture was adjusted to pH 2 with 4N hydrochloric acid. The precipitate was washed with water and then recrystallized from acetonitrile to obtain 1.54 g (yield: 41%) of 3-nitro-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-one having a melting point of 225°-227° C.

Provenance & Evidence