Hydrochloric Acid → 3-(3,4-Dichloro-phenyl)-dihydro-furan-2-one
反応式
[CH3:1][O:2][C:3](=[O:13])[CH2:4][C:5]1[CH:10]=[CH:9][C:8]([Cl:11])=[C:7]([Cl:12])[CH:6]=1.Br[CH2:15]CO.Cl>C1COCC1>[Cl:12][C:7]1[CH:6]=[C:5]([CH:4]2[CH2:15][CH2:1][O:2][C:3]2=[O:13])[CH:10]=[CH:9][C:8]=1[Cl:11]参加物
反応条件
- 温度
- 45 °C
実験手順
Heat [(CH3)3Si]2NLi (230 ml, 1.0M in THF) under N2 to 45° C. and add 3,4 dichlorophenyl acetic acid methyl ester (40 g, 0.183 moles) dissolved in 60 ml of dry THF dropwise over 2 h. Stir the solution at 45° C. for another 2.5 h. Cool the solution to room temperature, add a dry THF solution (30 ml.) of THP-protected Br(CH2)2OH dropwise over 1 h., and stir the solution for 24 h. Cool the solution in an ice bath and quench the reaction by adding, dropwise, 250 ml. of 1.0M aqueous HCl. Extract the solution with Et2 O, wash the organic layer twice with 1.0M aqueous HCl, then with water, and dry over anhydrous Na2SO4. Remove the solvent, dissolve the residue in CH3OH and add 0.5 g of pTSA. Stir the solution at room temperature overnight, remove the solvent, add CH3OH (500 ml) and stir for 6 h. Remove the solvent again, add more CH3OH (500 ml.), stir overnight and remove the solvent. Dissolve the resulting oil in CH2Cl2 (1200 ml.), wash twice with saturated aqueous NaHCO3, then water, and dry over anhydrous Na2SO4. Remove the solvent in vacuo. Purify the reaction mixture by flash chromatography (SiO2) using EtOAc: hexanes (3:7) as eluent. Yield: 22 g. Cl-MS: 231 (100%), 233 (65%).
後処理
- temperatureCool the solution to room temperature
- stirringstir the solution for 24 h
- temperatureCool the solution in an ice bath
- customquench
- customthe reaction
- additionby adding
- extractionExtract the solution with Et2 O
- washwash the organic layer twice with 1.0M aqueous HCl
- dry with materialwith water, and dry over anhydrous Na2SO4
- customRemove the solvent
- dissolutiondissolve the residue in CH3OH
- additionadd 0.5 g of pTSA
- stirringStir the solution at room temperature overnight
- customremove the solvent
- additionadd CH3OH (500 ml)
- stirringstir for 6 h
- customRemove the solvent again
- additionadd more CH3OH (500 ml.)
- stirringstir overnight
- customremove the solvent
- dissolutionDissolve the resulting oil in CH2Cl2 (1200 ml.)
- washwash twice with saturated aqueous NaHCO3
- dry with materialwater, and dry over anhydrous Na2SO4
- customRemove the solvent in vacuo
- customPurify the reaction mixture by flash chromatography (SiO2)
出典と根拠
- ORDレコード
- ord-cc5388282a324eeaa4b2929d691ae157
- 出典データセット
- uspto-grants-1998_11
- 特許番号
- US05840725
反応ノート
読み込み中…