Hydrochloric Acid → 2-(4'-(6-Carbamoyl-3,5-dimethylpyrazin-2-yl)-2,6-difluorobiphenyl-4-yl)acetic acid

Participants

Reaction Conditions

Reaction Steps

Powdered potassium hydroxide (0.039 g, 0.70 mmol) was added in one portion to methyl 2-(4′-(6-carbamoyl-3,5-dimethylpyrazin-2-yl)-2,6-difluorobiphenyl-4-yl)acetate (Intermediate 24-1; 0.096 g, 0.23 mmol) in tert-butanol (2.00 mL) at 40° C. under nitrogen. The resulting suspension was stirred at 40° C. for 20 minutes. A thick precipitate formed so the reaction was quenched with aq 1M HCl (1.4 mL, 1.40 mmol) and the resulting solution stirred for a further 20 minutes before being evaporated to dryness. The resulting solid was partitioned between water (5 mL) and EtOAc (15 mL). The organic layer was separated and the aqueous re-extracted with EtOAc (2×5 mL). The combined organics were washed with brine (15 mL), dried over MgSO4 and evaporated in vacuo to give product. The crude product was purified by preparative HPLC (Waters—Xbridge Prep C18 5 μm), using decreasingly polar mixtures of water (containing 0.1% formic acid) and {MeOH(3):MeCN(1)} as eluents. Fractions containing the desired compound were evaporated to dryness to afford 2-(4′-(6-carbamoyl-3,5-dimethylpyrazin-2-yl)-2,6-difluorobiphenyl-4-yl)acetic acid (0.052 g, 56.0%) as a colourless solid.

Provenance & Evidence