Hydrochloric Acid → 3'-Fluoro-4'-methoxy-[1,1'-biphenyl]-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 50 g (0.20 mol) of the above 4-acetyl 3'-fluoro-4'-methoxy biphenyl in 2 l of dioxane was added 1000 ml of an aqueous solution of sodium hypobromite (prepared from 338 g of sodium hydroxide and 486 g of bromine) over about 4 hours while cooling to not higher than 10° C., which was stirred at 25°-30° C. for about 3 hours. Thereafter, an aqueous saturated solution of sodium bisulfite was added to decompose the excessive amount of sodium hypobromite and then added with a concentrated hydrochloric acid to adjust pH to approximately 1. After the leaving over two nights, the precipitated crystal was filtered and recrystallized with ethanol and further with acetic acid to obtain 43 g (yield: 85%) of 3'-fluoro-4'-methoxybiphenyl-4-carboxylic acid.

Provenance & Evidence