Acetic Acid → 2-Iodo-4,5-dimethoxybenzaldehyde

HRID 1029828

反応式

HRID 1029828 の反応式
C[O:2][CH:3](OC)[C:4]1[CH:9]=[C:8]([O:10][CH3:11])[C:7]([O:12][CH3:13])=[CH:6][C:5]=1Br.C([Li])CCC.[I:22]I.C(O)(=O)C>O1CCCC1>[I:22][C:5]1[CH:6]=[C:7]([O:12][CH3:13])[C:8]([O:10][CH3:11])=[CH:9][C:4]=1[CH:3]=[O:2]

参加物

6

反応物 4

HCID 176Acetic AcidHCID 807IodineHCID 110771461-Bromo-2-(dimethoxymethyl)-4,5-dimethoxybenzeneHCID 178418339Butyllithium

生成物 1

HCID 110117632-Iodo-4,5-dimethoxybenzaldehyde収率 72.7%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
-70 °C

実験手順

2-Bromo-4,5-dimethoxybenzaldehyde dimethylacetal (59 g) is dissolved in tetrahydrofuran and thereto is added 2.5M n-butyllithium (89 ml) under cooling at -70° C. The reaction mixture is kept below -50° C. for 30 minutes and thereto is added dropwise a solution of iodine (51.4 g) in tetrahydrofuran below -50° C. The mixture is kept at the same temperature for 15 minutes and thereto are added aqueous acetic acid to adjust the pH of the solution at 2. The mixture is allowed to stand at room temperature overnight, and the solvent is distilled off from the reaction mixture. The residue is dissolved in ethyl acetate. The solution is washed and dried, and the solvent is distilled off. The residue is crystallized from ethyl acetate to give 2-iodo-4,5-dimethoxybenzaldehyde (43 g). M.p. 139°-141° C.

後処理

  1. waitThe mixture is kept at the same temperature for 15 minutes
  2. waitto stand at room temperature overnight
  3. distillationthe solvent is distilled off from the reaction mixture
  4. dissolutionThe residue is dissolved in ethyl acetate
  5. washThe solution is washed
  6. customdried
  7. distillationthe solvent is distilled off
  8. customThe residue is crystallized from ethyl acetate

出典と根拠

ORDレコード
ord-d731c7e1c8b64cfe8a960d3ca7563084
出典データセット
uspto-grants-1992_04
特許番号
US05103023

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