O1CCC[CH2:2]1.[Cl:6][C:7]1[CH:16]=[C:15]2[C:10]([CH2:11][CH2:12][C:13](=[O:30])[N:14]2[CH:17]2[CH2:22][CH2:21][N:20]([C:23]([O:25][C:26]([CH3:29])([CH3:28])[CH3:27])=[O:24])[CH2:19][CH2:18]2)=[N:9][CH:8]=1.C[Si](C)(C)[N-][Si](C)(C)C.[Li+].CI>O.C(OCC)(=O)C>[Cl:6][C:7]1[CH:16]=[C:15]2[C:10]([CH2:11][CH:12]([CH3:2])[C:13](=[O:30])[N:14]2[CH:17]2[CH2:22][CH2:21][N:20]([C:23]([O:25][C:26]([CH3:27])([CH3:29])[CH3:28])=[O:24])[CH2:19][CH2:18]2)=[N:9][CH:8]=1To a tetrahydrofuran solution (195 ml) of tert-butyl 4-(7-chloro-2-oxo-3,4-dihydro-1,5-naphthyridin-1(2H)-yl)piperidine-1-carboxylate (13.0 g) was added dropwise at −78° C. a tetrahydrofuran solution (1 M, 39.1 ml) of lithium hexamethyldisilazide. After stirring at the same temperature for 30 minutes, a tetrahydrofuran solution (65 ml) of methyl iodide (2.65 ml) was added dropwise. After stirring at the same temperature for 10 minutes and under ice cooling for 1 hour, ethyl acetate and water were added to the reaction solution, and the solution was separated. The organic layer was dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to afford tert-butyl 4-(7-chloro-3-methyl-2-oxo-3,4-dihydro-1,5-naphthyridin-1(2H)-yl)piperidine-1-carboxylate (12.2 g).
読み込み中…
