Diethyl Ether → 7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-one

Participants

Reaction Steps

In 16 ml of ethyl orthoformate was suspended 3.21 g of methyl 2-hydroxy-4-methylsulfonylamino-5-phenoxyphenyl ketone. To the mixture being ice-cooled was dropwise added 2.15 g of a 70% aqueous perchloric acid solution in 10 minutes. Stirring was conducted for 30 minutes at 20°-25° C. 50 ml of diethyl ether was added thereto. The resulting crystal was collected by filtration. The crystal was mixed with 50 ml of water, and the mixture was refluxed for 2 minutes and then cooled to room temperature. The resulting crystal was collected by filtration and recrystallized from acetonitrile to obtain 2.90 g (yield: 87.6%) of 7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-one.

Provenance & Evidence