4-[[2-(1,1-Dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid, methyl ester → 4-[[2-(1,1-Dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid
反応式
[CH3:1][C:2]([CH3:22])([O:4][C:5](=[O:21])[CH2:6][O:7][C:8]1[CH:13]=[CH:12][C:11]([CH2:14][CH:15]([CH3:20])[C:16]([O:18][CH3:19])=[O:17])=[CH:10][CH:9]=1)[CH3:3]>C(OCC)C>[CH3:22][C:2]([CH3:3])([O:4][C:5](=[O:21])[CH2:6][O:7][C:8]1[CH:9]=[CH:10][C:11]([CH2:14][CH:15]([CH3:20])[C:16]([O:18][CH3:19])=[O:17])=[CH:12][CH:13]=1)[CH3:1].[CH3:22][C:2]([CH3:3])([O:4][C:5](=[O:21])[CH2:6][O:7][C:8]1[CH:13]=[CH:12][C:11]([CH2:14][CH:15]([CH3:20])[C:16]([OH:18])=[O:17])=[CH:10][CH:9]=1)[CH3:1]参加物
反応物 1
生成物 2
試薬・触媒・溶媒 1
実験手順
Dissolve 4-[[2-(1,1-dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid, methyl ester (15.0 g, 48.6 mmol) in ethyl ether (50 mL) and adsorb onto silica gel (45 g). Evaporate the solvent under a stream of nitrogen and add pH 7 phosphate buffer (1500 mL of a 0.1M solution) followed by lipase P-30 (15 g). Maintain a ph of 7 by the addition of 1M sodium hydroxide. Stir for 24 hours, filter through silica gel and rinse the filter cake with chloroform (500 mL). Separate the aqueous phase and extract with chloroform (4×300 mL). Dry (MgSO4) the combined organic phases and evaporate the solvent in vacuo. Purify by flash chromatography (10% methanol/chloroform) to give (-)-4-[[2-(1,1-dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid, methyl ester (6.43 g, 91% ee) and (+)-4-[[2-(1,1-dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid (6.59 g, 90% ee after reesterification with diazomethane).
後処理
- customEvaporate the solvent under a stream of nitrogen
- additionadd pH 7 phosphate buffer (1500 mL of a 0.1M solution)
- temperatureMaintain a ph of 7
- additionby the addition of 1M sodium hydroxide
- filtrationfilter through silica gel
- washrinse the filter cake with chloroform (500 mL)
- customSeparate the aqueous phase
- extractionextract with chloroform (4×300 mL)
- dry with materialDry (MgSO4) the combined organic phases
- customevaporate the solvent in vacuo
- customPurify by flash chromatography (10% methanol/chloroform)
出典と根拠
- ORDレコード
- ord-a170be48060e4b5ca2fc2d26093eae75
- 出典データセット
- uspto-grants-1993_05
- 特許番号
- US05208240
反応ノート
読み込み中…