p-Toluenesulfonic acid monohydrate → [(Z)-4-((R)-2-hydroxymethyl-6-oxo-piperidin-1-yl)-but-2-enyloxy]-acetic acid ethyl ester
反応式
O.C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:13]([O:15][C:16](=[O:37])[CH2:17][O:18][CH2:19]/[CH:20]=[CH:21]\[CH2:22][N:23]1[C:28](=[O:29])[CH2:27][CH2:26][CH2:25][C@@H:24]1[CH2:30][O:31]C(OCC)C)[CH3:14]>CCO>[CH2:13]([O:15][C:16](=[O:37])[CH2:17][O:18][CH2:19]/[CH:20]=[CH:21]\[CH2:22][N:23]1[C:28](=[O:29])[CH2:27][CH2:26][CH2:25][C@@H:24]1[CH2:30][OH:31])[CH3:14]参加物
4
反応物 2
生成物 1
試薬・触媒・溶媒 1
実験手順
p-Toluenesulfonic acid hydrate (267 mg, 1.40 mmol) was added to a solution of {(Z)-4-[(R)-2-(1-ethoxyethoxymethyl)-6-oxo-piperidin-1-yl]-but-2-enyloxy}-acetic acid ethyl ester (from example 1, step 2, 477 mg, 1.33 mmol) in EtOH (6 mL). After 18 h at rt, the reaction was concentrated in vacuo and quenched with saturated aqueous NaHCO3 (20 mL). The mixture was extracted with CH2Cl2 (3×15 mL). The combined organic phase was dried (Na2SO4), filtered and concentrated in vacuo. Purification of the residue by flash column chromatography on silica gel (CH2Cl2 →3% MeOH/CH2Cl2, gradient) afforded 290 mg (76%) of [(Z)-4((R)-2-hydroxymethyl-6-oxo-piperidin-1-yl)-but-2-enyloxy]-acetic acid ethyl ester.