Hydrochloric Acid → 4-Fluorosalicylic acid

HRID 457950

反応式

HRID 457950 の反応式
F[C:2]1[CH:10]=[C:9]([F:11])[CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[OH-:12].[Na+].Cl>CN1CCN(C)C1=O.O>[F:11][C:9]1[CH:10]=[C:2]([OH:12])[C:3](=[CH:7][CH:8]=1)[C:4]([OH:6])=[O:5]

参加物

6

反応物 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 741022,4-Difluorobenzoic acid

生成物 1

HCID 676614-Fluorosalicylic acid収率 68.1%

試薬・触媒・溶媒 2

HCID 962Water溶媒HCID 66611,3-Dimethyl-2-imidazolidinone溶媒

反応条件

温度
135 °C

実験手順

A solution of 2,4-difluorobenzoic acid (100 g, 0.63 mol) in 1,3-dimethyl-2-imidazolidinone (1,400 mL, 0.45 M) was treated with sodium hydroxide (88 g, 2.2 mol) and heated to 135° C. After stirring for 4 h, the solution was cooled 0° C., disolved in water (100 mL), and transferred to a 5 L Erlenmeyer flask and carefully treated with aq HCl (2,800 mL, 2 N). After filtering off the crude product, the precipitate was disolved in ethyl acetate, dried over sodium sulfate and decolorizing charcol, and filtered. The solution was concentrated under reduced pressure and recrystallized from ethyl acetate and heptane to give 4-fluorosalicylic acid (2 crops, 67 g, 68%) as off-white needles. mp: 188–189° C.; Rf 0.26 (20% methanol in dichloromethane).

後処理

  1. temperaturethe solution was cooled 0° C.
  2. filtrationAfter filtering off the crude product
  3. dry with materialdried over sodium sulfate
  4. filtrationfiltered
  5. concentrationThe solution was concentrated under reduced pressure
  6. customrecrystallized from ethyl acetate and heptane

出典と根拠

ORDレコード
ord-b43b9eeea7ec4070abc3591f782f46ff
出典データセット
uspto-grants-2007_03
特許番号
US07189749B2

関連ノート

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