Yield:648408-62-2 100%

Reaction Conditions:

with triethylamine in tetrahydrofuran at 0 - 20; for 24 h;

Steps:

1 Example 1: [00231] Ethyl 2-((2,6-difluorophenyl)amino)-2-oxoacetate (3):

Example 1: [00231] Ethyl 2-((2,6-difluorophenyl)amino)-2-oxoacetate (3): Triethylamine (27.2 mL, 193.8 mmol, 1 equiv.) was added to a solution of 2,6-difluoroaniline (25.0 g, 193.8 mmol, 1 equiv.) in THF (1 L) at 0-5°C. Ethyl oxalyl chloride (21.6 mL, 193.8 mmol, 1 equiv.) was added dropwise over 60 minutes, while maintaining the temperature <5°C. The reaction was warmed to room temperature and stirred for 24 hours. The reaction was filtered through celite, the celite was washed with methyl /-butyl ether (500 mL) and the combined organic layers were washed with a IN HCI (2 x 200 mL) and water (400 mL). The organic layer was dried over sodium sulfate, filtered and concentrated under reduced pressure to give the desired product as a beige oil (44.8 g, quantitative yield).

References:

WO2020/181165,2020,A1 Location in patent:Paragraph 00231; 00280