反应详情

温度

55 °C

To a solution of tert-butyl 4-(3-methoxy-2,2-dimethyl-3-oxopropyl)piperazine-1-carboxylate (58.0 g, 193.08 mmoles) in isopropyl alcohol (150 mL) add a 4M dioxane solution of hydrogen chloride ((4 equiv); 193.08 mL, 772.31 mmoles) over 15 minutes, observing gas evolution and a fine precipitate. Heat at 55° C. for 3 h to give a white precipitate. Cool to 10° C. and collect the white solid by filtration, wash with further isopropyl alcohol (30 mL), then EtOAc. Dry in a vacuum oven at 45° C. for 1 h to give methyl 2,2-dimethyl-3-(piperazin-1-yl)propanoate dihydrochloride (31 g, 59% yield). MS (m/z): =201.1 (M+1).

1. customto give a white precipitate
2. temperatureCool to 10° C.
3. customcollect the white solid
4. filtrationby filtration
5. washwash with further isopropyl alcohol (30 mL)
6. customDry in a vacuum oven at 45° C. for 1 h