HOAt → [(2R,5S)-5-(6-Amino-3-fluoro-pyridin-2-yl)-2,5-dimethyl-2-trifluoromethyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester

Participants

Reaction Steps

A mixture of [(2R,5R)-5-(6-amino-3-fluoro-pyridin-2-yl)-2,5-dimethyl-2-trifluoromethyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester (406 mg, 0.999 mmol), 3-chloro-5-cyanopicolinic acid (201 mg, 1.099 mmol), HOAt (245 mg, 1.798 mmol) and EDC hydrochloride (287 mg, 1.499 mmol) was stirred in DMF (10.2 ml) at rt for 44 hours. The reaction mixture was diluted with toluene and washed with sat. aq. sodium bicarbonate solution, water and brine, dried over sodium sulfate, filtered and evaporated. The crude product (595 mg) was chromatographed over silicagel (toluene: ethyl acetate 9:1) to yield the title compound: 455 mg (76% yield).

Provenance & Evidence