반응 #85367

반응 방정식

(E)-2-((2-Pyridin-3-yl)hydrazono)acetic acid hydrochloride

sodium chloride

N-Chlorosuccinimide

acrylonitrile

potassium bicarbonate

→

desired product

수율 71.9%

3-Chloro-1-(pyridine-3-yl)-4,5-dihydro-1H-pyrazole-5-carbonitrile

수율 71.9%

용매

Water

ethyl acetate

반응 조건

후처리

1. 1
   여과the mixture was filtered through Celite®
2. 2
   세척The filter cake was washed with ethyl acetate (40 mL)
3. 3
   기타the layers were separated
4. 4
   기타dried
5. 5
   농축concentrated
6. 6
   기타to afford a residue
7. 7
   기타The resulting residue was purified by flash column chromatography

실험 절차

(E)-2-((2-Pyridin-3-yl)hydrazono)acetic acid hydrochloride (2.00 g, 9.42 mmol) was stirred in ethyl acetate (47.1 mL). N-Chlorosuccinimide (2.36 g, 19.3 mmol), acrylonitrile (1.85 mL, 28.3 mmol) and potassium bicarbonate (2.86 g, 28.3 mmol) were added. Water (0.05 mL) was added and the mixture was stirred at room temperature for 18 hours. Saturated aqueous sodium chloride (brine, 50 mL) was added and the mixture was filtered through Celite®. The filter cake was washed with ethyl acetate (40 mL) and the layers were separated. The organic layers were combined, dried and concentrated to afford a residue. The resulting residue was purified by flash column chromatography using 80-100% ethyl acetate/hexanes as eluent to afford the desired product as an orange solid (1.40 g, 57.5%): 1H NMR (400 MHz, CDCl3) δ 8.51 (dd, J=2.9, 0.7 Hz, 1H), 8.33 (dd, J=4.7, 1.4 Hz, 1H), 7.51 (ddd, J=8.4, 2.9, 1.4 Hz, 1H), 7.30 (ddd, J=8.5, 4.7, 0.8 Hz, 1H), 5.06 (dd, J=11.3, 5.9 Hz, 1H), 3.64 (dd, J=17.4, 11.3 Hz, 1H), 3.51 (dd, J=17.4, 5.9 Hz, 1H); 13C NMR (101 MHz, CDCl3) δ 143.34, 142.79, 140.11, 136.16, 123.92, 121.93, 115.80, 51.39, 43.04; ESIMS m/z 207 ([M+H]+).

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