C(NC(C)C)(C)C.C([Li])CCC.CCCCCC.[Cl:19][C:20]1[C:25]([Cl:26])=[CH:24][N:23]=[C:22]2[N:27]([S:30]([C:33]3[CH:39]=[CH:38][C:36]([CH3:37])=[CH:35][CH:34]=3)(=[O:32])=[O:31])[CH:28]=[CH:29][C:21]=12.C([N-]C(C)C)(C)C.[Li+].[I:48]I>O1CCCC1>[Cl:19][C:20]1[C:25]([Cl:26])=[CH:24][N:23]=[C:22]2[N:27]([S:30]([C:33]3[CH:39]=[CH:38][C:36]([CH3:37])=[CH:35][CH:34]=3)(=[O:32])=[O:31])[C:28]([I:48])=[CH:29][C:21]=12To a solution of diisopropylamine (4.85 mL, 34.1 mmol) in tetrahydrofuran (50 mL) at −10° C. under nitrogen was added dropwise 2.5M n-butyllithium in hexane (13.62 mL, 34.1 mmol) and the mixture was stirred at −10° C. for 30 minutes. A solution of Example 229A (8.3 g, 24.33 mmol) in tetrahydrofuran (220 mL) cooled to −78° C. was treated with the lithium diisopropylamide solution dropwise over 20 minutes and the mixture was stirred for 50 minutes at −78° C. A solution of iodine (8.64 g, 34.1 mmol) in tetrahydrofuran (30 mL) was added and the mixture was stirred for 20 minutes at −78° C. and allowed to warm to room temperature. The reaction was quenched with saturated aqueous sodium thiosulfate and extracted with ethyl acetate (150 mL). The organic layer was washed with water and brine, dried over sodium sulfate, filtered, and concentrated. The residue was purified by flash chromatography on silica gel (AnaLogix IntelliFlash 280) eluting with a gradient of 30-60% ethyl acetate in hexanes. The solid was triturated with 100 mL 15% ethyl acetate/hexane, filtered and dried under vacuum to afford the title compound. MS (ESI+) m/z 466.7 (M+H)+.
読み込み中…
