Hydrochloric Acid → 5-Fluoro-2,4-dimethoxybenzoic acid

HRID 2357121노트

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HRID 2357121 반응식
[CH3:1][O:2][C:3]1[CH:10]=[C:9]([O:11][CH3:12])[C:8]([F:13])=[CH:7][C:4]=1[C:5]#N.[OH-:14].[Na+].Cl.C[OH:18]>>[F:13][C:8]1[C:9]([O:11][CH3:12])=[CH:10][C:3]([O:2][CH3:1])=[C:4]([CH:7]=1)[C:5]([OH:18])=[O:14]

참가 물질

5

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온도
0 °C

실험 절차

A solution of 3.1 g (17.2 mmol) of 2,4-dimethoxy-5-fluorobenzonitrile and 100 mL of 6N aqueous sodium hydroxide in 200 mL of methanol was stirred at reflux overnight, cooled to 0° C., acidified to pH 1-2 with 6N aqueous hydrochloric acid, and partitioned between ethyl acetate and brine. The organic extract was dried over Na2SO4, and the solvents were removed in vacuo to give crude 2,4-dimethoxy-5-fluorobenzoic acid as a light-yellow solid. Recrystallization from ethyl acetate and hexane afforded 3.2 g (93%) of 6 as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 12.4 (s, 1H), 7.49 (d, 1H, J=12 Hz), 6.83 (d, 1H, J=7.2 Hz), 3.92 (s, 3H), 3.84 (s, 3H); 13C NMR (75 MHz, DMSO-d6) δ 165.5, 165.5, 156.7, 151.1, 151.0, 146.3, 143.2, 117.9, 117.6, 111.2, 111.1, 99.3, 56.6, 56.4; 19F NMR (282 MHz, DMSO-d6) δ −146.2 (dd, 1F); mass spectrum, calculated for C9H9FO4 (MH+) 201.1, Found 200.9.

후처리

  1. temperatureat reflux overnight
  2. custompartitioned between ethyl acetate and brine
  3. extractionThe organic extract
  4. dry with materialwas dried over Na2SO4
  5. customthe solvents were removed in vacuo
  6. customto give crude 2,4-dimethoxy-5-fluorobenzoic acid as a light-yellow solid
  7. customRecrystallization from ethyl acetate and hexane

출처 및 근거

ORD 기록
ord-ee60833a195647db9af6c1d8e3658ad9
출처 데이터셋
uspto-grants-2010_07
특허 번호
US07759459B2

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