反应详情

A solution of 5-bromonicotinic acid (4 g, 0.02 mol) in thionyl chloride (25 mL) was heated under reflux for 4 h. The excess thionyl chloride was removed under reduced pressure to provide 5-bromonicotinyl chloride which was used without further purification. To 5-bromonicotinyl chloride (3.5 g, 13.6 mmol) was added glycine ethylester (2.1 g, 20.3 mmol) and diisopropyl ethyl amine (2.6 g, 20.1 mmol) in THF (70 mL) and the reaction mixture stirred at RT for 16 h. The reaction mixture was diluted with EtOAc and washed with brine solution. The combined organic layers were dried over Na2SO4, filtered and concentrated under reduced pressure and the residue was purified by silica gel column chromatography using 25% EtOAc in hexane to provide ethyl 2-(5-bromonicotinamido)acetate 1.2 g (33%) as a brown solid. LCMS Method T: retention time 1.28 min; [M+1]=288.2

1. customwas used without further purification
2. washwashed with brine solution
3. dry with materialThe combined organic layers were dried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customthe residue was purified by silica gel column chromatography