反应详情

温度

-78 °C

To a solution of tert-butyl 4-[4-(2,2-dibromovinyl)-1,3-thiazol-2-yl]piperidine-1-carboxylate (1.26 g, 2.79 mmol) in anhydrous tetrahydrofuran (25 ml) was added dropwise at −78° C. a mixture of 1.6M-n-butyllithium-hexane solution (5.2 ml, 8.4 mmol) and anhydrous tetrahydrofuran (10 ml). After stirring at −78° C. for 2 hrs, 1.25M hydrogen chloride-ethanol solution (6.7 ml, 8.4 mmol) was added dropwise to the reaction mixture. The mixture was warmed to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was concentrated, and the concentrated residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9→1:4) to give tert-butyl 4-(4-ethynyl-1,3-thiazol-2-yl)piperidine-1-carboxylate (553 mg, yield 68%) as a yellow solid.

1. temperatureThe mixture was warmed to room temperature
2. extractionthe mixture was extracted with ethyl acetate
3. concentrationThe extract was concentrated
4. customthe concentrated residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9→1:4)