反应详情

To a stirred solution of methyl (2S,4S)-1-tert-butoxycarbonyl-4-phenoxy-2-pyrrolidinylcarboxylate (5.31 g, 16.5 mmol) in THF (132 ml) was added 0.25 N NaOH (132 ml, 33.0 mmol) at room temperature. The resulting mixture was stirred over night. After removal of the solvent, the mixture was acidified by the addition of 1 N HCl and extracted with CHCl3. The combined extracts were washed with brine, dried over Na2SO4 and evaporated. The residue was recrystallized from n-hexane-CHCl3, to give (2S, 4S)-1-tert-butoxycarbonyl-4-phenoxy-2-pyrrolidinylcarboxylic acid (2.96 g, 58%) as a white powder. 1H-NMR (DMSO-d6) δ 1.36 (s, 9H), 2.16 (d, J=13.2 Hz, 1H), 2.56 (m, 1H ), 3.46 (m, 1H), 3.71 (dt, J=12.0, 5.4 Hz, 1H), 4.26 (dt, J=9.5, 7.1 Hz, 1H), 4.99 (m, 1H), 6.85 (m, 2H), 6.94 (t, J=7.3 Hz, 1H), 7.28 (t, J=7.3 Hz, 1H).

1. customAfter removal of the solvent
2. additionthe mixture was acidified by the addition of 1 N HCl
3. extractionextracted with CHCl3
4. washThe combined extracts were washed with brine
5. dry with materialdried over Na2SO4
6. customevaporated
7. customThe residue was recrystallized from n-hexane-CHCl3