Sulfur → Flurbiprofen

Participants

Reaction Conditions

Reaction Steps

A mixture of 5.00 g of α-methyl-4-cyclohexyl-3-fluorophenylacetic acid (m.p. 83° to 84° C.) and 2.3 g of sulphur in 10 ml of diphenyl ether was subjected to heating with stirring at 250° C. for 6 hours. The resulting reaction liquid was dissolved in acetone, and the insoluble substances were removed by filtration. The filtrate was poured into an aqueous sodium hydroxide solution. The resulting mixture was repeatedly washed with benzene, and hydrochloric acid was added to the aqueous layer. The crystals thus precipitated were collected by filtration, and recrystallized from a mixed benzene-n-hexane solvent to obtain 2.2 g of α-methyl-2-fluoro-4-biphenylylacetic acid (m.p. 112° to 114° C.).

Provenance & Evidence