反应详情

3-[4-(tert-Butoxycarbonyl)piperazin-1-yl]-3-oxopropionic acid methyl ester (35) (3.30 g; 11.5 mmol) is dissolved in 2:2:2 tetrahydrofuran: water: methanol. Lithium chloride (2.76 g; 115.3 mmol) is added and the mixture is stirred for 1 hour at ambient temperature. The solution is concentrated in vacuo to remove the tetrahydrofuran and methanol. The concentrate is poured onto citric acid solution (115 mL) and extracted with ethyl acetate (230 mL). The organic layer is washed with water (3×115 mL) and brine (1×115 mL), then dried over magnesium sulfate, filtered and concentrated in vacuo to afford the desired product as a solid. ESMS: MH+ 273.0

1. concentrationThe solution is concentrated in vacuo
2. customto remove the tetrahydrofuran and methanol
3. additionThe concentrate is poured onto citric acid solution (115 mL)
4. extractionextracted with ethyl acetate (230 mL)
5. washThe organic layer is washed with water (3×115 mL) and brine (1×115 mL)
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo