反応 #632016

反応方程式

1(R)-tert-butoxycarbonylamino-2(S)-vinyl-cyclopropanecarboxylic acid ethyl ester

LiOH

→

desired compound

収率 87.3%

1(R)-tert-butoxycarbonylamino-2(S)-vinyl-cyclopropanecarboxylic acid

収率 87.3%

溶媒

THF

methanol

water

反応条件

後処理

1. 1
   その他quenched with 1N NaOH (15 mL) and water (20 mL)
2. 2
   洗浄The resulting mixture was washed with ethyl acetate (20 mL)
3. 3
   抽出the organic phase was extracted with 20 mL 0.5N NaOH
4. 4
   抽出extracted with ethyl acetate (3×40 mL)
5. 5
   洗浄The combined organic extracts were washed with brine
6. 6
   乾燥dried (MgSO4)
7. 7
   ろ過filtered
8. 8
   濃縮concentrated

実験手順

To a solution of 1(R)-tert-butoxycarbonylamino-2(S)-vinyl-cyclopropanecarboxylic acid ethyl ester (3.28 g, 13.2 mmol) in THF (7 mL) and methanol (7 mL) was added a suspension of LiOH (1.27 g, 53.0 mmol) in water (14 mL). The mixture was stirred overnight at room temperature and quenched with 1N NaOH (15 mL) and water (20 mL). The resulting mixture was washed with ethyl acetate (20 mL), and the organic phase was extracted with 20 mL 0.5N NaOH. The combined aqueous phases were acidified with 1N HCl to pH 4 and extracted with ethyl acetate (3×40 mL). The combined organic extracts were washed with brine, dried (MgSO4), filtered and concentrated to provide the desired compound as a white solid (2.62 g, 87%). 1HNMR: (DMSO-d6) δ 1.22-1.26 (m, 1H), 1.37 (s, 9H), 1.50-1.52 (m, 1H), 2.05 (q, J=9 Hz, 1H), 5.04 (d, J=10 Hz, 1H), 5.22 (d, J=17 Hz, 1H), 5.64-5.71 (m, 1H), 7.18, 7.53 (s, NH (rotamers), 12.4 (br s, 1H)); LC-MS (retention time: 1.67 minutes, method B), MS m/z 228 (M++H).

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