Реакция #1116042

Уравнение реакции

triethylamine

Oxalyl chloride

mono-methyl fumarate

3

Tert-Butyl 4-(benzoyloxyamino)butylcarbamate

NH4Cl

→

4

Выход 72.0%

(E)-Methyl 4-(benzoyloxy(4-(tert-butoxycarbonylamino)butyl)amino)-4-oxobut-2-enoate

Выход 72.0%

Растворители

CH2Cl2

DMF

CH2Cl2

Условия реакции

Обработка

1. 1
   workup.STIRRINGstirred for another 30 minutes
2. 2
   workup.STIRRINGThe reaction was stirred at room temperature for 2 h
3. 3
   Экстракцияthe aqueous layer was extracted with ethyl acetate
4. 4
   Сушкаdried over anhydrous Na2SO4
5. 5
   Фильтрацияfiltered
6. 6
   Концентрированиеconcentrated in vacuo
7. 7
   Другоеto give a crude oil, which
8. 8
   Другоеwas purified by column chromatography on silica gel (hexanes/ethyl acetate=10:1)

Методика

Oxalyl chloride (0.39 mL, 4.5 mmol) was added dropwise to a solution of mono-methyl fumarate (0.64 g, 4.9 mmol) in distilled CH2Cl2 (7 mL) at 0° C., then a drop of anhydrous DMF was added. The resulting mixture was stirred at this temperature for 20 minutes before it was warmed to room temperature and stirred for another 30 minutes. A solution of 3 (1.16 g, 3.75 mmol) in distilled CH2Cl2 (3 mL) was added at 0° C., followed by the addition of freshly distilled triethylamine (1.05 mL, 7.5 mmol) and DMAP (0.049 g, 0.40 mmol). The reaction was stirred at room temperature for 2 h. A saturated aqueous solution of NH4Cl was added and the aqueous layer was extracted with ethyl acetate, dried over anhydrous Na2SO4, filtered and concentrated in vacuo to give a crude oil, which was purified by column chromatography on silica gel (hexanes/ethyl acetate=10:1) to afford 4 (1.14 g, 2.7 mmol) as a colorless oil in 72% yield: IR (thin film): 3368, 2976, 1768, 1713, 1520, 1240, 1170, 1006 cm−1; 1H NMR (400 MHz, CDCl3): δ 8.15-8.03 (m, 2H), 7.68 (t, J=7.5 Hz, 1H), 7.52 (t, J=7.7 Hz, 2H), 7.13 (d, J=15.7 Hz, 1H), 6.92 (d, J=15.4 Hz, 1H), 4.65-4.56 (br, 1H), 3.89 (t, J=6.9 Hz, 2H), 3.73 (s, 3H), 3.18-3.13 (m, 2H), 1.75-1.70 (m, 2H), 1.61-1.52 (m, 2H), 1.39 (s, 9H) ppm; 13C NMR (101 MHz, CDCl3): δ 165.80, 164.62, 156.15, 135.03, 133.03, 131.28, 130.37, 129.20, 126.24, 79.31, 52.43, 52.39, 48.38, 40.20, 28.54, 27.48, 24.50 ppm. HRMS (m/z): [M+Na]+ calcd. for C21H28N2NaO7, 443.1788; found, 443.1792.

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