Triethylamine → Ethyl 2-[6-azido-2-(2,4-difluorophenylamino)-5-fluoronicotinoyl]acetate

Participants

Reaction Steps

In 10 ml of anhydrous acetonitrile was suspended 1.05 g of ethyl 2-[2-(2,4-difluorophenylamino)-5-fluoro-6-hydroxynicotinoyl]acetate, and 450 mg of triethylamine and 1.22 g of diphenylphosphoryl azide were added thereto with ice-cooling, after which the resulting mixture was subjected to reaction at room temperature for 4 hours. To this reaction mixture were added 50 ml of ethyl acetate and 50 ml of water, and the organic layer was separated, and then dried over anhydrous magnesium sulfate. The solvent was removed by ditillation under reduced pressure, and the residue thus obtained was purified by a column chromoatography [Wako Silica Gel C-200, eluant: benzene] to obtain 550 mg (yield 48.9%) of ethyl 2-[6-azido-2-(2,4-difluorophenylamino)-5-fluoronicotinoyl]acetate having a melting point of 130°-131° C.

Provenance & Evidence