methyl 2-chloro-1,7-naphthyridine-3-carboxylate synthesis

Yield:1124194-70-2 92%

Reaction Conditions:

with trichlorophosphate at 120; for 5 h;

Steps:

232.1 Step-1 : Synthesis of methyl 2-chloro-l,7-naphthyridine-3-carboxylate

[0746] A solution of methyl 2-hydroxy-l,7-naphthyridine-3-carboxylate (500 mg, 2.45 mmol) in POCh (5.0 mL) was stirred at 120 °C for 5 hours. The reaction mixture was concentrated under vacuum. The aqueous solution was quenched with water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum. The residue was purified by flash chromatography on silica gel with 0-50% ethyl acetate in petroleum ether to afford the title compound (500 mg, 92%) as a yellow solid.

References:

WO2020/243459,2020,A1 Location in patent:Paragraph 0746