反应详情

To a solution of 96 mg (0.51 mmol) 4-bromo-pyridine-2,6-diamine in 2.4 ml MeOH was added 121 mg (0.56 mmol) O-mesitylenesulfonylhydroxylamine (prepared from ethyl o-mesitylene-sulfonylacetohydroxamate and HClO4 (70%)) in 0.6 ml MeOH at −5° C. and after 15min 71 mg (0.56 mmol) benzaldehyde and stirred for 30 min. The addition of 4.8 ml 1N KOH was followed by extraction with ethylacetate, drying of the organic layer with Na2SO4, and removal of the volatile components. The residue was purified by column chromatography on silica eluting with ethylacetate and hexane (2:3). 58 mg(39%) of 7-bromo-2-phenyl-[1,2,4]triazolo[1,5-a]pyridin-5-ylamine were isolated, MS m/e (%): 290 (M++2, 44).

1. extractionwas followed by extraction with ethylacetate
2. dry with materialdrying of the organic layer with Na2SO4, and removal of the volatile components
3. customThe residue was purified by column chromatography on silica eluting with ethylacetate and hexane (2:3)