反応 #2358586

反応方程式

3-iodo-1-(oxan-2-yl)-1H-pyrazole-4-carboxylic acid

→

(3-iodo-1-(oxan-2-yl)-1H-pyrazol-4-yl)methanol

収率 47.3%

溶媒

THF

THF

反応条件

後処理

1. 1
   workup.STIRRINGThe reaction was stirred overnight at room temperature
2. 2
   その他quenched by the addition of 300 mL of saturated NH4Cl solution
3. 3
   抽出The resulting mixture was extracted with 3×1000 mL of dichloromethane
4. 4
   乾燥The combined organic layers was dried over anhydrous sodium sulfate
5. 5
   濃縮concentrated under vacuum
6. 6
   その他The residue was purified on a silica gel column
7. 7
   洗浄eluted with ethyl acetate/petroleum ether (1:1)

実験手順

To a solution of 3-iodo-1-(oxan-2-yl)-1H-pyrazole-4-carboxylic acid (28 g, 86.93 mmol, 1.00 equiv) in anhydrous THF (300 mL) maintained under nitrogen at 5° C. was added a 1M solution of BH3 in THF (300 mL) dropwise with stirring. The reaction was stirred overnight at room temperature and then quenched by the addition of 300 mL of saturated NH4Cl solution. The resulting mixture was extracted with 3×1000 mL of dichloromethane. The combined organic layers was dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was purified on a silica gel column eluted with ethyl acetate/petroleum ether (1:1) to give 12.67 g (47%) of (3-iodo-1-(oxan-2-yl)-1H-pyrazol-4-yl)methanol as a white solid. 1H NMR (400 MHz, DMSO-d6): δ 7.73 (s, 1H), 5.37-5.34 (m, 1H), 4.92 (s, 1H), 4.20 (d, J=3.6 Hz, 2H), 3.89-3.88 (m, 1H), 3.65-3.57 (m, 1H), 2.09-2.00 (m, 1H), 1.99-1.90 (m, 2H), 1.69-1.61 (m, 1H), 1.49-1.46 (m, 2H) ppm. LCMS (method A, ESI): RT=1.16 min, m/z=309.0 [M+H]+.

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