Iodine → Benzyl 3-(hydroxymethylene)-4-oxo-spiro[chromane-2,4'-piperidine]-1'-carboxylate
反応式
II.C([O:5][CH:6](OCC)[CH:7]1[C:16]2([CH2:21][CH2:20][N:19]([C:22]([O:24][CH2:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[O:23])[CH2:18][CH2:17]2)[O:15][C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[C:8]1=[O:32])C>CC(C)=O>[OH:5][CH:6]=[C:7]1[C:16]2([CH2:21][CH2:20][N:19]([C:22]([O:24][CH2:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[O:23])[CH2:18][CH2:17]2)[O:15][C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[C:8]1=[O:32]参加物
4
反応条件
- 温度
- 35 °C
実験手順
Iodine (2.88 g, 11.4 mmol) was slowly added to a solution of benzyl 3-(diethoxymethyl)-4-oxospiro[chroman-2,4′-piperidine]-1′-carboxylate (20.6 g, 45.4 mmol) in acetone (515 mL) and the mixture was stirred at 35° C. overnight. The reaction mixture was concentrated and the residue was purified by silica gel column chromatography (0-40% ethyl acetate in hexane) to afford benzyl 3-(hydroxymethylene)-4-oxospiro[chroman-2,4′-piperidine]-1′-carboxylate (15.2 g, 88%). ESI-MS m/z calc. 379.1. found 380.3 (M+1)+; Retention time: 2.00 minutes (3 min run).