Dimethylformamide → 2,4-Difluoro-3-formylbenzoic acid

HRID 79025

反応式

HRID 79025 の反応式
CN(CCN(C)C)C.C([Li])(CC)C.[F:14][C:15]1[CH:23]=[C:22]([F:24])[CH:21]=[CH:20][C:16]=1[C:17]([OH:19])=[O:18].CN([CH:28]=[O:29])C>C1COCC1>[F:14][C:15]1[C:23]([CH:28]=[O:29])=[C:22]([F:24])[CH:21]=[CH:20][C:16]=1[C:17]([OH:19])=[O:18]

参加物

6

反応物 4

HCID 6228DimethylformamideHCID 8037N,N,N',N'-TetramethylethylenediamineHCID 741022,4-Difluorobenzoic acidHCID 178418400CID 53628100

生成物 1

HCID 583743952,4-Difluoro-3-formylbenzoic acid収率 11%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
-75 °C

実験手順

A solution of TMEDA (10.5 mL, 70 mmol) in THF (50 mL) was cooled to <−80° C. and treated with sec-butyllithium (50 mL, 70 mmol). A solution of 2,4-difluorobenzoic acid (5.0 g, 31.6 mmol) in THF was added dropwise maintaining the temperature below −80° C. The reaction mixture was allowed to warm to −75° C. and treated with DMF (15 mL), the mixture then allowed to warm to 0° C. before quenching the reaction with water. The aqueous layer was separated, acidified to pH ˜2 (concentrated HCl) and extracted twice with diethyl ether. The combined organic extracts were dried (Na2SO4), filtered and concentrated in vacuo to give a yellow oil. The crude product was crystallized from cyclohexane/diethyl ether to give the title compound as a yellow solid (670 mg, 11%). 1H NMR (CDCl3, 400 MHz) 10.40 (1 H, s), 8.31 (1 H, ddd, J=8.96, 8.02, 6.08 Hz), 7.12 (1 H, td, J=9.09, 1.42 Hz).

後処理

  1. temperaturemaintaining the temperature below −80° C
  2. temperatureto warm to 0° C.
  3. custombefore quenching
  4. customthe reaction with water
  5. customThe aqueous layer was separated
  6. extractionextracted twice with diethyl ether
  7. dry with materialThe combined organic extracts were dried (Na2SO4)
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo
  10. customto give a yellow oil
  11. customThe crude product was crystallized from cyclohexane/diethyl ether

出典と根拠

ORDレコード
ord-a47cc2a286804b1e87ac2eff419cddd0
出典データセット
uspto-grants-2014_09
特許番号
US08841462B2

関連ノート

読み込み中…