反应详情

Methyl 4-(tert-butoxycarbonylamino)-2-(4-chlorophenyl)-2-methylbutanoate (720 mg, 2.11 mmol) was dissolved in THF (4.2 mL) and water (1.8 mL). The mixture was treated with LiOH—H2O (265 mg, 6.32 mmol) and allowed to stir overnight to completion by LCMS analysis. The mixture was diluted with water and washed twice with diethyl ether (discarded). The aqueous was treated with 3M HCl solution until a pH of about 2 to about 3 (white ppt) and extracted with ethyl acetate several times. The combined organic portions were washed with water, then brine, separated, dried over MgSO4, filtered, and concentrated in vacuo to afford 4-(tert-butoxycarbonylamino)-2-(4-chlorophenyl)-2-methylbutanoic acid as a colorless oil (684 mg, 99%). LCMS (APCI+) [M+H]+ 326.0; Rt: 2.26 min.

1. washwashed twice with diethyl ether (discarded)
2. additionThe aqueous was treated with 3M HCl solution until a pH of about 2 to about 3 (white ppt)
3. extractionextracted with ethyl acetate several times
4. washThe combined organic portions were washed with water
5. custombrine, separated
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo