C(O[BH-](OC(=O)C)OC(=O)C)(=O)C.[Na+].[Br:15][C:16]1[CH:17]=[C:18]([CH3:28])[C:19]([C:22]2[CH2:23][CH2:24][NH:25][CH2:26][CH:27]=2)=[N:20][CH:21]=1.[O:29]1[CH2:34][CH2:33][C:32](=O)[CH2:31][CH2:30]1.[OH-].[Na+]>O1CCCC1.CCCCCC>[Br:15][C:16]1[CH:17]=[C:18]([CH3:28])[C:19]([C:22]2[CH2:23][CH2:24][N:25]([CH:32]3[CH2:33][CH2:34][O:29][CH2:30][CH2:31]3)[CH2:26][CH:27]=2)=[N:20][CH:21]=1
Sodium triacetoxyborohydride (5.25 g) was added at room temperature to a solutions of 5-bromo-3-methyl-1′,2′,3′,6′-tetrahydro-2,4′-bipyridine (5.23 g) and tetrahydro-4H-pyran-4-one (2.07 g) in tetrahydrofuran (50 ml) and n-hexane (20 ml), and stirred at the same temperature. After completion of the reaction, 1N aqueous solution of sodium hydroxide was added under ice cooling and extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting residue was purified with silica gel column chromatography (chloroform/methanol) and washed with diethyl ether and n-hexane to give 5-bromo-3-methyl-1′-(tetrahydro-2H-pyran-4-yl)-1′,2′,3′,6′-tetrahydro-2,4′-bipyridine (3.1 g) as a pale yellow solid.
読み込み中…
