反应详情

To a suspension of 6-fluoro-2-phenyl-[1,2,4]triazolo[1,5-a]pyridine-7-carboxylic acid (495 mg, 1.92 mmol) and triethylamine (805 μl, 5.77 mmol) in tert-butanol (28.9 ml) is added diphenyl phosphorazidate (623 μl, 2.89 mmol) at 25° C. The resulting mixture is heated to reflux and stirred for 18 hours. The crude material is loaded on silicagel and purified by flash chromatography on a 20 g silica column using heptane/ethyl acetate 30-100% as eluent affording tert-butyl 6-fluoro-2-phenyl-[1,2,4]triazolo[1,5-a]pyridin-7-ylcarbamate (252 mg, 39.9%) as a light yellow solid. Mp.: 180-8° C. MS: m/z=329.2 (M+H+).

1. temperatureThe resulting mixture is heated
2. temperatureto reflux
3. custompurified by flash chromatography on a 20 g silica column