反应详情

To a stirred solution of methyl 4-(4-(2-tert-butylphenyl)-piperazin-1-yl)-4-oxobutanoate obtained in Example 52 (0.245 g, 0.74 mmol) in THF (2.0 mL) was added a solution of lithium hydroxide (0.053 g, 2.20 mmol) in 4:1 MeOH/H2O (2.5 mL) at room temperature. After 2 h the reaction mixture was concentrate under reduced pressure. The residue was acidified to pH 1-2 with 1.0 M hydrochloric acid and extracted with ethyl acetate (3×20 mL). The combined organics were washed with saturated sodium chloride (20 mL), dried (Na2SO4), filtered and concentrated under reduced pressure to provide a residue. Trituration of the residue with 1:3 CH3CN/H2O provided 4-(4-(2-tert-butylphenyl)piperazin-1-yl)-4-oxobutanoic acid (0.217 g, 92%) as a white solid, mp 175-176° C.

1. concentrationAfter 2 h the reaction mixture was concentrate under reduced pressure
2. extractionextracted with ethyl acetate (3×20 mL)
3. washThe combined organics were washed with saturated sodium chloride (20 mL)
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customto provide a residue