반응 #1951056

반응 방정식

4-fluorobenzyl bromide

trimethyl phosphite

→

(4-fluoro-benzyl)-phosphonic acid dimethyl ester

수율 67.5%

용매

ethyl acetate

반응 조건

후처리

1. 1
   기타at 90° C.
2. 2
   기타overnight
3. 3
   온도to cool to ambient temperature
4. 4
   세척The solution was washed with saturated sodium bicarbonate (350 mL)
5. 5
   건조The organic phase was dried with magnesium sulfate
6. 6
   여과filtered
7. 7
   농축concentrated by rotatry evaporation
8. 8
   기타The resulting crude product was purified by flash silica chromatrography

실험 절차

4-fluorobenzyl bromide (25 mL, 0.20 mol) was added to a stirred solution of trimethyl phosphite (35.9 mL, 0.30 mol) at ambient temperature, under a nitrogen atmosphere. The resulting solution was heated at 110° C. for six hours, and then at 90° C. overnight. The reaction mixture was allowed to cool to ambient temperature and then ethyl acetate (350 mL) was added. The solution was washed with saturated sodium bicarbonate (350 mL) and then with saturated brine (2×350 mL). The organic phase was dried with magnesium sulfate, filtered, and concentrated by rotatry evaporation. The resulting crude product was purified by flash silica chromatrography using 0-35% acetonitrile in ethyl acetate as eluant to yield (4-fluoro-benzyl)-phosphonic acid dimethyl ester (29.44 g, 135 mmol, 66% yield) as a colorless oil. 1H NMR (400 MHz, DMSO) δ 7.33-7.28 (m, 2H); 7.17-7.12 (dd, 2H); 3.61-3.58 (d, 6H); 3.31-3.24 (d, 2H); ESMS (m/z): (M+1)+ found, 219.

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