Sodium Hydroxide → 6-(3-Chloro-4-fluoro-phenyl)-8-methyl-8-vinyl-5,6,7,8-tetrahydro-[1,5]naphthyridine-2-carboxylic acid

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Reaction Steps

To a solution of 6-(3-chloro-4-fluoro-phenyl)-8-methyl-8-vinyl-5,6,7,8-tetrahydro-[1,5]naphthyridine-2-carboxylic acid methyl ester (300 mg, 0.8 mmol) in tetrahydrofuran (2 mL) and methanol (2 mL) was added 3 N sodium hydroxide (1 mL). The reaction mixture was stirred at room temperature for 16 hours, and then diluted with water (10 mL), extracted with diethyl ether (20 mL). The organic layer was discarded. The aqueous layer was acidified with concentrated hydrochloric acid to pH 4 and extracted with ethyl acetate (40 mL×3), and the combined organics were dried over anhydrous Na2SO4. The solvent was removed in vacuo and purified by preparative HPLC to afford 6-(3-chloro-4-fluoro-phenyl)-8-methyl-8-vinyl-5,6,7,8-tetrahydro-[1,5]naphthyridine-2-carboxylic acid (180 mg, 62.7%) as a yellow oil. MS (ESI+) [(M+H)+] 347.2.

Provenance & Evidence