Carbon Dioxide → 3-Hydroxy-7-methoxy-3-methyl-phthalide

HRID 22174

反応式

HRID 22174 の反応式
[CH3:1][O:2][C:3]1[CH:13]=[CH:12][CH:11]=[C:5]2[C:6]([O:8][C:9](=[O:10])[C:4]=12)=[O:7].[C:14](O)(=O)CC(O)=O.C(N(CC)CC)C.C(=O)=O>O>[OH:7][C:6]1([CH3:14])[C:5]2[C:4](=[C:3]([O:2][CH3:1])[CH:13]=[CH:12][CH:11]=2)[C:9](=[O:10])[O:8]1

参加物

6

反応物 4

HCID 280Carbon DioxideHCID 867Malonic AcidHCID 8471TriethylamineHCID 2911934-Methoxy-1,3-dihydro-2-benzofuran-1,3-dione

生成物 1

HCID 199274383-Hydroxy-7-methoxy-3-methyl-phthalide

試薬・触媒・溶媒 1

HCID 962Water溶媒

反応条件

温度
73 °C

実験手順

5.4 g of 3-methoxy-phthalic acid anhydride [see A. V. R. Rao et al., Indian J. Chem. 20B, 248 ff. (1981)], 4.7 g of malonic acid and 9 ml of triethylamine are heated slowly. The suspension becomes stirrable at 55° C. and, from 68° C., moderately vigorous CO2 evolution occurs. The internal temperature is maintained at 73° C. until gas evolution ceases (about 1 hour) and the reaction mixture is then heated at reflux temperature (internal temperature 85° C.) for a further 4 hours. When it has cooled, the reaction mixture is treated with water and extracted with ethyl acetate. The aqueous phase is then adjusted to pH 1.7 and extracted three times with fresh ethyl acetate, dried over anhydrous sodium sulfate and concentrated by evaporation under reduced pressure. Fractional crystallisation (ethyl acetate/n-hexane) yields 3-hydroxy-7-methoxy-3-methyl-phthalide, m.p. 156°-158° C.; IR spectrum (CHCl3): C=O 1772 cm-1.

後処理

  1. custombecomes stirrable at 55° C. and, from 68° C.
  2. temperaturethe reaction mixture is then heated
  3. temperatureat reflux temperature (internal temperature 85° C.) for a further 4 hours
  4. temperatureWhen it has cooled
  5. extractionextracted with ethyl acetate
  6. extractionextracted three times with fresh ethyl acetate
  7. dry with materialdried over anhydrous sodium sulfate
  8. concentrationconcentrated by evaporation under reduced pressure
  9. customFractional crystallisation (ethyl acetate/n-hexane)

出典と根拠

ORDレコード
ord-321bce556ec0470c8cdb100a6ae37967
出典データセット
uspto-grants-1995_06
特許番号
US05428002

関連ノート

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