Ethyl Acetate → 2-(2,4-Difluoro-phenoxy)-5-nitro-isonicotinic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

To 2,4 difluorophenol (Aldrich Chemical Co.) (2.68 mL, 1.1 eq) in THF (60 mL) at 0° C. was added sodium hydride (60% in oil) (1.123 g, 1.1 eq), and the resulting mixture was stirred from 0° C. to room temperature over 1 hour. This solution was then added to compound (1A) (5.79 g, 26.7 mmol), and the resulting mixture was heated at reflux for 2 hours. TLC analysis confirmed that the reaction was complete, and the mixture was cooled to room temperature. EtOAc (300 mL) and water (100 mL) were added, the resulting mixture was partitioned, and the layers were separated. The organic layer was washed with water (3×100 mL) and brine (1×100 mL). Then the EtOAc layer was dried over magnesium sulfate, filtered, concentrated, and pumped to give the titled compound (1B) as an off-white powder (7.99 g, M+=310, Mp=90.2–91.4° C.)

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