Synthesis
The general procedure for the synthesis of 4'-trifluoromethyl-diphenyl-4-carboxylic acid from 4-bromobenzoic acid and 4-trifluoromethylphenylboronic acid was as follows: the reaction was carried out according to General Method D. 4-Bromobenzoic acid (10 g, 49.4 mmol), 4-trifluoromethylphenylboronic acid (14.17 g, 74.61 mmol), tetrakis(triphenylphosphine)palladium (5.7 g, 4.974 mmol) and 2N Na2CO3 aqueous solution (150 mL, 149.2 mmol) were mixed in 500 mL of toluene. Upon completion of the reaction, the reaction mixture was neutralized with 2N HCl and subsequently filtered. The resulting solid was dissolved in ethyl acetate and purified by a short silica gel column to give 9.7 g (75% yield) of the target product 4'-trifluoromethyl-diphenyl-4-carboxylic acid as a white solid.
References
[1] Tetrahedron Letters, 2005, vol. 46, # 34, p. 5751 - 5754
[2] Green Chemistry, 2010, vol. 12, # 1, p. 150 - 158
[3] Patent: WO2004/14844, 2004, A2. Location in patent: Page 179; 181
[4] Journal of Medicinal Chemistry, 2007, vol. 50, # 20, p. 4939 - 4952
[5] Journal of Medicinal Chemistry, 1997, vol. 40, # 20, p. 3144 - 3150
