Benzeneacetic acid, 3,4-dimethoxy-, methyl ester → alpha-[5-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]pentyl]-3,4-dimethoxybenzeneacetic acid methyl ester

HRID 274025

反応式

HRID 274025 の反応式
COC1[CH:11]=[C:10]2[C:6](CNC2)=[CH:5][C:4]=1[OH:12].[CH3:13][O:14][C:15](=[O:27])[CH2:16][C:17]1[CH:22]=[CH:21][C:20]([O:23][CH3:24])=[C:19]([O:25][CH3:26])[CH:18]=1.[Na].BrCCCC[CH2:34][Si:35]([C:38]([CH3:41])([CH3:40])[CH3:39])(C)[CH3:36]>O1CCCC1.C(OCC)C.O>[CH3:13][O:14][C:15](=[O:27])[CH:16]([CH2:11][CH2:10][CH2:6][CH2:5][CH2:4][O:12][Si:35]([C:38]([CH3:41])([CH3:40])[CH3:39])([CH3:36])[CH3:34])[C:17]1[CH:22]=[CH:21][C:20]([O:23][CH3:24])=[C:19]([O:25][CH3:26])[CH:18]=1

参加物

8

反応条件

温度
-78 °C

実験手順

To a solution, -78° C. under argon, of 2 38 g of 3,4-dimethoxyphenyl acetic acid methyl ester in 30 ml of tetrahydrofuran is added 12.45 ml of 1.0M sodium hexamethylsidilazide. The solution is stirred at -78° C. for 5 minutes and then warmed to 0° C. for 1 hour. To this solution is added 3.5 g of (5-bromopentyl)(1,1-dimethylethyl)dimethyl silane. The reaction mixture is allowed to warm to room temperature and stirred for 12 hours. The mixture is diluted with diethyl ether and water, the layers are separated and the organic layer is washed with saturated sodium chloride, dried and concentrated in vacuo. The residue is purified by chromatography (silica gel: hexane/ethyl acetate,5/1) to give 2.6 g of the desired product as a clear oil.

後処理

  1. temperaturewarmed to 0° C. for 1 hour
  2. temperatureto warm to room temperature
  3. stirringstirred for 12 hours
  4. customthe layers are separated
  5. washthe organic layer is washed with saturated sodium chloride
  6. customdried
  7. concentrationconcentrated in vacuo
  8. customThe residue is purified by chromatography (silica gel: hexane/ethyl acetate,5/1)

出典と根拠

ORDレコード
ord-278b8b799112408cad48b628991a6464
出典データセット
uspto-grants-1995_02
特許番号
US05387685

関連ノート

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