Brucine → (S)-1-(2,6-dimethylphenyl)-3-(2-methylallyl)-5-oxo-pyrrolidine-3-carboxylic acid
反応式
[CH3:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH3:8])[C:3]=1[N:9]1[C:13](=[O:14])[CH2:12][C:11]([CH2:18][C:19]([CH3:21])=[CH2:20])([C:15]([OH:17])=[O:16])[CH2:10]1.COC1C=C2[C@@]34[C@@H]5C[C@H]6C(CN5CC3)=CCO[C@H]3CC(=O)N([C@H]4[C@@H]63)C2=CC=1OC>CC(O)C>[CH3:8][C:4]1[CH:5]=[CH:6][CH:7]=[C:2]([CH3:1])[C:3]=1[N:9]1[C:13](=[O:14])[CH2:12][C@:11]([CH2:18][C:19]([CH3:21])=[CH2:20])([C:15]([OH:17])=[O:16])[CH2:10]1参加物
反応条件
- 温度
- 75 °C
実験手順
To a mixture of 1-(2,6-dimethylphenyl)-3-(2-methylallyl)-5-oxo-pyrrolidine-3-carboxylic acid (prepared from step b, 9 g, 31.36 mmol) and brucine (12.37 g, 31.35 mmol) was added iPrOH (75 mL) and heated with stirring at 75° C. until it became a clear solution, which was then allowed to cool to room temperature slowly. The resulting white solid was filtered and discarded. The filtrate was then diluted with Et2O (100 mL) and washed with 2 N HCl (2×100 mL), dried (Na2SO4) and concentrated under reduced pressure to obtain (S)-1-(2,6-dimethyl-phenyl)-3-(2-methyl-allyl)-5-oxo-pyrrolidine-3-carboxylic acid (550 mg, enantiomeric ratio: 9:1, with the enantiomeric ratio determined using a RegisWhelk® chiral analytical column and 10% EtOH in hexanes isocratic solvent system, flow rate: 1 mL/min, 30 min run). Further recrystallization of the above carboxylic acid derivative from hot toluene/dioxane (9:1, 14 mL) enriched the enantiomeric ratio to 99.2:0.8 and afforded 430 mg of (S)-1-(2,6-dimethylphenyl)-3-(2-methylallyl)-5-oxo-pyrrolidine-3-carboxylic acid.
後処理
- temperatureheated
- temperatureto cool to room temperature slowly
- filtrationThe resulting white solid was filtered
- additionThe filtrate was then diluted with Et2O (100 mL)
- washwashed with 2 N HCl (2×100 mL)
- dry with materialdried (Na2SO4)
- concentrationconcentrated under reduced pressure
出典と根拠
- ORDレコード
- ord-6a72544d51f843218c7ab79b9e6aed5a
- 出典データセット
- uspto-grants-2014_05
- 特許番号
- US08716494B2
反応ノート
読み込み中…