C([BH3-])#N.[Na+].[NH2:5][C:6]1[CH:11]=[C:10]([CH3:12])[C:9]([F:13])=[CH:8][C:7]=1[OH:14].O=[C:16]1[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]1.C(O)(=O)C>ClCCl>[F:13][C:9]1[C:10]([CH3:12])=[CH:11][C:6]([NH:5][CH:16]2[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]2)=[C:7]([OH:14])[CH:8]=1Polymer supported sodium cyanoborohydride (794 mg, 3.41 mmol) was added to a solution of commercially available 2-amino-5-fluoro-4-methylphenol (241 mg, 1.71 mmol), 1,1-dimethylethyl 4-oxo-1-piperidinecarboxylate (350 mg, 1.76 mmol) and acetic acid (0.489 mL, 8.53 mmol) in dichloromethane (10 mL). The mixture was heated by microwave at 100° C. for 30 min before being filtered and concentrated by rotary evaporation to give a green oil. The residue was purified via chromatography (silica, dichloromethane to 0.5% ammonia/9.5% methanol/90% dichloromethane) to give 1,1-dimethylethyl 4-[(4-fluoro-2-hydroxy-5-methylphenyl)amino]-1-piperidinecarboxylate (593 mg, 73% purity, 78% yield) as a brown oil.
読み込み中…
