Methyl iodide → 1,3-Cyclopentanedione, 2,2-dimethyl-

HRID 406792ノート

反応式

HRID 406792 の反応式
[CH3:1][CH:2]1[C:6](=[O:7])[CH2:5][CH2:4][C:3]1=[O:8].CI.[OH-].[K+].O1CCOC[CH2:14]1>O>[CH3:1][C:2]1([CH3:14])[C:6](=[O:7])[CH2:5][CH2:4][C:3]1=[O:8]

参加物

6

反応物 4

HCID 6328Methyl iodide3 回HCID 130052-Methyl-1,3-cyclopentanedioneHCID 14797Potassium Hydroxide3 回HCID 312751,4-Dioxane3 回

生成物 1

HCID 197631,3-Cyclopentanedione, 2,2-dimethyl-収率 93%

試薬・触媒・溶媒 1

HCID 962Water溶媒3 回

実験手順

The published procedure was followed. (Agosta, W. C.; Smith, A. B. J. Org. Chem. 1970, 35, 3856) A mixture of 2-methyl-1,3-cyclopentanedione (10.025 g, 89.4 mmol, Aldrich), methyl iodide (6.0 mL, 96.4 mmol, Aldrich), and KOH (5.097 g, 90.8 mmol) in H2O (25 mL)/dioxane (75 mL) was heated at reflux. After 5 h, a solution of KOH (2 g) and MeI (2.4 mL) in H2O (5 mL)/dioxane (15 mL) was added and after another 3 h at reflux the solution was allowed to stir at room temperature overnight. In the morning, the reaction was continued by addition of a solution of KOH (2 g) and MeI (2.4 mL) in H2O (5 mL)/dioxane (15 mL) and heating at reflux. After 4 h, the mixture was allowed to cool to room temperature and was extracted with ether (1×100 mL, 3×75 mL). The combined ether extracts were evaporated, the residue combined with HCl (50 mL 10%), and the resulting mixture was placed in a 120° C. oil bath until boiling was observed (ca. 15 min.). The mixture was then allowed to cool to room temperature, was neutralized by addition of NaHCO3 solution (150 mL, saturated) and the resulting mixture then extracted with CH2Cl2 (4×75 mL). The combined CH2Cl2 solution was dried (MgSO4), filtered and evaporated to leave a brown oil (10.474 g, 83 mmol, 93%) which was used directly in the next step.

後処理

  1. temperaturewas heated
  2. temperatureat reflux
  3. temperatureat reflux the solution
  4. temperatureheating
  5. temperatureat reflux
  6. waitAfter 4 h
  7. temperatureto cool to room temperature
  8. extractionwas extracted with ether (1×100 mL, 3×75 mL)
  9. customThe combined ether extracts were evaporated
  10. customwas placed in a 120° C.
  11. custom(ca. 15 min.)
  12. temperatureto cool to room temperature
  13. additionwas neutralized by addition of NaHCO3 solution (150 mL, saturated)
  14. extractionthe resulting mixture then extracted with CH2Cl2 (4×75 mL)
  15. dry with materialThe combined CH2Cl2 solution was dried (MgSO4)
  16. filtrationfiltered
  17. customevaporated

出典と根拠

ORDレコード
ord-ac82d255f510421a93b1801e71b1d2aa
出典データセット
uspto-grants-2014_06
特許番号
US08754122B2

反応ノート

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