Triacetoxyperiodinane → Benzyl 2,2-dimethyl-3-oxocyclopentylcarbamate
反応式
CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O.[OH:23][CH:24]1[CH2:28][CH2:27][CH:26]([NH:29][C:30](=[O:39])[O:31][CH2:32][C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=2)[C:25]1([CH3:41])[CH3:40]>ClCCl>[CH3:40][C:25]1([CH3:41])[C:24](=[O:23])[CH2:28][CH2:27][CH:26]1[NH:29][C:30](=[O:39])[O:31][CH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1参加物
4
実験手順
Dess-Martin periodinane (9.49 g, 22.39 mmol) was added to a solution of cis/trans mixture of benzyl 3-hydroxy-2,2-dimethylcyclopentylcarbamate (3.93 g, 14.92 mmol, from Step 1 of Intermediate 21) in dichloromethane (150 mL) at room temperature. After 2 h at room temperature, the mixture was filtered to remove the precipitate. The filtrate was washed with 10% aqueous sodium thiosulfate (10 mL), saturated sodium bicarbonate (20 mL), brine (20 mL), dried (MgSO4), filtered and concentrated. Silica gel chromatography, eluting with 10 to 50% ethyl acetate in hexanes, gave benzyl 2,2-dimethyl-3-oxocyclopentylcarbamate (3.20 g, 82% yield). 1H NMR (400 MHz, chloroform-d) δ ppm 7.30-7.74 (5 H, m), 4.97-5.33 (2 H, m), 4.60-4.93 (1 H, m), 2.17-2.42 (2 H, m), 1.47-1.82 (2 H, m), 1.12 (3 H, s), 0.91 (3 H, s); MS (ES+) m/z: 262.3 (M+H); HPLC retention time: 2.643 min (analytical HPLC Method A).