Hydrochloric Acid → 2-(3,4-Dimethoxyphenyl)-7-hydroxy-4H-chromen-4-one

HRID 1743340ノート

反応式

HRID 1743340 の反応式
[OH-].[Li+].[CH3:3][C:4]([C:6]1[CH:7]=[CH:8][C:9]([OH:13])=[CH:10][C:11]=1[OH:12])=[O:5].[CH3:14][O:15][C:16]1[CH:17]=[C:18]([CH:22]=[CH:23][C:24]=1[O:25][CH3:26])[C:19](Cl)=O.Cl>C1COCC1>[CH3:14][O:15][C:16]1[CH:17]=[C:18]([CH:22]=[CH:23][C:24]=1[O:25][CH3:26])[C:19]1[O:12][C:11]2[C:6]([C:4](=[O:5])[CH:3]=1)=[CH:7][CH:8]=[C:9]([OH:13])[CH:10]=2

参加物

6

反応物 4

HCID 313Hydrochloric AcidHCID 3939Lithium HydroxideHCID 69902',4'-DihydroxyacetophenoneHCID 77070Veratroyl chloride

生成物 1

HCID 53785182-(3,4-Dimethoxyphenyl)-7-hydroxy-4H-chromen-4-one

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
0 °C

実験手順

Dry, pulverulent lithium hydroxide (18 mmol, 3.6 equivalents) is added in one portion to a well-stirred solution of 2,4-dihydroxyacetophenone (5 mmol) in dry THF (5 ml) under an argon atmosphere at −78° C. The reaction mixture is stirred at −78° C. for one hour and subsequently at about 0° C. for two hours. After the mixture has been re-cooled to −78° C., a solution of 3,4-dimethoxybenzoyl chloride (5.9 mmol) in THF (10 ml) is added in one portion. The mixture is stirred at −78° C. for one hour and at room temperature for 4 hours until the starting material has disappeared. The reaction mixture is emptied into a mixture of ice (150 g) and concentrated HCl (5 ml) and extracted with chloroform (3×50 ml). The solvents are removed from the dried extracts, and the residue is dried under reduced pressure for 24 hours. Glacial acetic acid (30 ml) and sulfuric acid (0.2 ml) are added to the residue, and the mixture is heated at 95–100° C. for from 30 minutes to one hour under an argon atmosphere. Approximately one third of the acetic acid is stripped off, and the residue is emptied into water. The precipitated product is filtered, washed and dried and recrystallised in methanol, giving 3′,4′-dimethoxy-7-hydroxyflavone. 1H NMR (250 MHz, DMSO-d6): δ=3.85 (d, 6 H), 6.85–8.00 (m, 7 H), 10.72 (s, 1 H); 13C NMR (250 MHz, DMSO-d6): δ=56.08 (s), 56.22 (s), 102.95 (s), 105.82 (s), 109.76 (s), 112.11 (s), 115.19 (s), 116.51 (s), 119.38 (s), 123.97 (s), 126.80 (s), 149.40 (s), 152.10 (s), 157.79 (s), 162.41 (s), 162.94 (s), 176.70 (s); EI-MS (70 eV) m/e (rel. abund.)=298; UV (2-propanol): λ=236 nm, 332 nm.

後処理

  1. customDry
  2. temperatureAfter the mixture has been re-cooled to −78° C.
  3. stirringThe mixture is stirred at −78° C. for one hour and at room temperature for 4 hours until the starting material
  4. extractionextracted with chloroform (3×50 ml)
  5. customThe solvents are removed from the dried extracts
  6. customthe residue is dried under reduced pressure for 24 hours
  7. additionGlacial acetic acid (30 ml) and sulfuric acid (0.2 ml) are added to the residue
  8. temperaturethe mixture is heated at 95–100° C. for from 30 minutes to one hour under an argon atmosphere
  9. filtrationThe precipitated product is filtered
  10. washwashed
  11. customdried
  12. customrecrystallised in methanol

出典と根拠

ORDレコード
ord-a772936a976f4508bb2f3db2921f2fab
出典データセット
uspto-grants-2006_03
特許番号
US07009062B2

反応ノート

読み込み中…