Toluene → 5-Phenylnicotinic Acid

Participants

Reaction Steps

5-Bromonicotinic acid (500 mg, 2.48 mmol, 1 eq.), phenylboronic acid (454 mg, 3.71 mmol, 1.5 eq.), tetrakis(triphenylphosphine)palladium(0) (143 mg, 0.124 mmol, 0.05 eq.), and sodium carbonate (787 mg, 7.43 mmol, 3 eq.) were mixed in ethanol (5 mL), toluene (25 mL), and water (5 mL) at room temperature under nitrogen. The reaction was then refluxed for 20 hours. Worked up by adding water then stripping off the ethanol. Rinsed the aqueous layer 2 times with diethyl ether. Adjusted the aqueous layer pH=3 with conc. HCl. The acidic aqueous layer was extracted 3 times with ethyl acetate and a little THF. The ethyl acetate/THF layers were combined, dried over sodium sulfate and stripped to give 5-phenylnicotinic acid (332 mg) as a white solid. Yield=67%. LCMS detects (M+H)+=198.1.

Provenance & Evidence