Реакция #1884972

Уравнение реакции

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

LiOH

→

title compound

Выход 87.3%

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

Выход 87.3%

Растворители

THF

methanol

water

Условия реакции

Обработка

1. 1
   Другоеquenched with 1N NaOH (15 mL) and water (20 mL)
2. 2
   ПромывкаThe resulting mixture was washed with ethyl acetate (20 mL)
3. 3
   Экстракцияthe organic phase was extracted with 20 mL 0.5N NaOH
4. 4
   Экстракцияextracted with ethyl acetate (3×40 mL)
5. 5
   ПромывкаThe combined organic extracts were washed with brine
6. 6
   Сушкаdried (MgSO4)
7. 7
   Фильтрацияfiltered
8. 8
   Концентрированиеconcentrated

Методика

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 until pH 4 and extracted with ethyl acetate (3×40 mL). The combined organic extracts were washed with brine, dried (MgSO4), filtered and concentrated to yield the title compound as a white solid (2.62 g, 87%). 1H NMR: (DMSO-d6) 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)); MS m/z 228 (M++H).

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