反应详情

N-(tert-Butoxycarbonyl)piperazine (2.50 g; 13.4 mmol) and triethylamine (1.77 g; 2.43 mmol) are dissolved in methylene chloride (40 mL). The solution is cooled in an ice-bath and a solution of methyl 3-chloro-3-oxopropionate (2.02 g; 14.8 mmol) in 10 mL methylene chloride is added dropwise over a 10-minute period. The ice-bath is removed and the reaction mixture is stirred for 1 hour at room temperature. The reaction mixture is then poured onto ice-cold 0.1N HCl (100 mL) and extracted with methylene chloride (200 mL). The organic extract is washed with saturated sodium bicarbonate and water, dried over magnesium sulfate, filtered and concentrated in vacuo. The residue is purified by chromatography on silica gel (60%→80% ethyl acetate in hexanes) to afford the desired product as a white solid. ESMS: MH+ 287.2

1. temperatureThe solution is cooled in an ice-bath
2. customThe ice-bath is removed
3. additionThe reaction mixture is then poured onto ice-cold 0.1N HCl (100 mL)
4. extractionextracted with methylene chloride (200 mL)
5. extractionThe organic extract
6. washis washed with saturated sodium bicarbonate and water
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe residue is purified by chromatography on silica gel (60%→80% ethyl acetate in hexanes)