To 1-(4′-acetylbiphenyl-4-yl)cyclopropanecarboxylic acid ethyl ester (10.1 g, 33 mmol) in dioxane (200 mL) at ˜10° C. was added a solution of bromine (26.4 g, 165 mmol), sodium hydroxide (22.4 g, 561 mmol) in water (150 mL). The solution was stirred at room temperature for 30 minutes, poured into water (500 mL) and acidified with dilute hydrochloric acid. Sodium metabisulfite was added until the brown bromine color dissipated. The product was filtered and dried in a vacuum over overnight at 40° C. to yield 10 g of 4′-(1-(ethoxycarbonyl)cyclopropyl)biphenyl-4-carboxylic acid.
