C([Li])(C)(C)C.[Cl:6][C:7]1[CH:12]=[CH:11][C:10]([O:13][CH2:14][O:15][CH3:16])=[CH:9][N:8]=1.[I:17]I>C1COCC1.C(OCC)(=O)C.O>[Cl:6][C:7]1[CH:12]=[C:11]([I:17])[C:10]([O:13][CH2:14][O:15][CH3:16])=[CH:9][N:8]=1
Add tert-buty lithium (1.7 M in pentane, 72 mL, 123 mmol) to a solution of 2-chloro-5-methoxymethoxy-pyridine (10.8 g, 62 mmol) in THF (300 mL) at −70° C. dropwise over 10 min. Stir the resulting solution at −70° C. for 30 min. Add a solution of iodine (23 g, 92 mmol) in THF (150 mL) dropwise over 30 min. Stir the resulting solution at −70° C. for 1 hour. Remove the ice bath and allow the reaction to warm to room temperature. Dilute the mixture with ethyl acetate and water and isolate the phases. Extract the aqueous phase with two portions of ethyl acetate. Combine the organic extracts and wash with two portions of aqueous sodium thiosulfate, one portion of water, one portion of saturated aqueous sodium chloride, dry over sodium sulfate, filter and concentrate in vacuo. Triturate the resulting solid with hexane. Collect the solid by vacuum filtration and wash the solid with hexane. Dry the solid under vacuum to give the title compound (10.8 g, 58%) as a brown solid. 1H NMR (400 MHz, DMSO-d6) δ 8.08 (s, 1H), 7.98 (s, 1H), 5.43 (s, 2H), 3.40 (s, 3H).
読み込み中…
