Sodium Hydroxide → (R)-4-hydroxy-2-(3-benzyloxybenzyl)cyclopent-2-enone
反応式
C([O:4][C@@H:5]1[CH2:9][C:8](=[O:10])[C:7]([CH2:11][C:12]2[CH:17]=[CH:16][CH:15]=[C:14]([O:18][CH2:19][C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=3)[CH:13]=2)=[CH:6]1)(=O)C.[OH-].[Na+]>OP([O-])(O)=O.[K+].OP(O)(O)=O>[OH:4][C@@H:5]1[CH2:9][C:8](=[O:10])[C:7]([CH2:11][C:12]2[CH:17]=[CH:16][CH:15]=[C:14]([O:18][CH2:19][C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=3)[CH:13]=2)=[CH:6]1参加物
4
実験手順
(R)-3-(3-Benzyloxybenzyl)-4-oxocyclopent-2-enyl acetate (1.8 kg, 5.35 mol) was added to KH2PO4—H3PO4 buffer solution (20 L). The mixture was added Lipase derived from Pseudomonas cepacia and 1N NaOH was slowly added to the solution at room temperature to keep the ph=7˜7.5. After 8 hours, (R)-3-(3-Benzyloxybenzyl)-4-oxocycl opent-2-enyl acetate remained about 10%, The reaction mixture was filtered to remove Lipase and the filtrate was extracted with EtOAc, dried over MgSO4, and evaporated. The resulting residue was purified by chromatography on a silica gel column using hexane-EtOAc as eluent to give the (R)-4-hydroxy-2-(3-benzyloxybenzyl)cyclopent-2-enone as yellow oil: 1.3 kg (yield: 83%, >99% ee by HPLC using a chiral column)