Potassium Carbonate → 6-Fluoro-4-methoxy-biphenyl-3-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a flame dried flask containing degassed toluene (15.2 mL, 0.5 M) was added 5-bromo-4-fluoro-2-methoxy-benzoic acid methyl ester (2.0 g, 7.6 mmol), anhydrous K2CO3 (2.1 g, 15.2 mmol), phenylboronic acid (3.7 g, 30.4 mmol), and Pd(PPh3)4 (0.88 g, 0.76 mmol). Using a reflux condenser, the stirring mixture was heated to 110° C. for 3.5 h. The mixture was then cooled to room temperature, placed in an ice bath and H2O2 (30%, 10 mL) was slowly added. The ice bath was removed and the reaction was allowed to stir at room temperature for one hour. The mixture was then diluted with ether and washed successively with 2 N HCl and saturated aq NaCl. The organic layer was dried over Na2SO4, filtered, and concentrated to afford a brown oil. Purification by MPLC (10-100% ethyl acetate in heptane, 23 mL/min, 75 min) provided 6-fluoro-4-methoxy-biphenyl-3-carboxylic acid methyl ester (1.8 g, 91%) as a pale yellow solid: Rf 0.5 (40% ethyl acetate in heptane); 1H NMR (CDCl3, 300 MHz) δ 8.00 (d, J=9.0 Hz, 1H), 7.53-7.33 (m, 5H), 6.79 (d, J=12.6 Hz, 1H), 3.94 (s, 3H), 3.89 (s, 3H).

Provenance & Evidence