C([N-]C(C)C)(C)C.[Li+].[F:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][N:11]=1.Cl[C:17]([O:19][CH3:20])=[O:18].O>O1CCCC1>[F:9][C:10]1[C:15]([C:17]([O:19][CH3:20])=[O:18])=[CH:14][CH:13]=[CH:12][N:11]=12 M lithium diisopropyl amide (11.3 mL, 22.5 mmol) is slowly added over a solution of 2-fluoropyridine (2 g, 20.5 mmol) in tetrahydrofuran (90 mL) under nitrogen atmosphere at −78° C. After 4 h at that temperature methyl chloroformate (1.9 mL, 24.6 mmol) is added and the mixture is stirred for an additional hour at −78° C. and allowed to reach room temperature overnight. Reaction mixture is slowly poured over water and extracted in diethyl ether. Organic layer is washed with brine, dried over sodium sulfate and solvent is evaporated in vacuo. Residue is purified by normal phase Isco chromatography eluting with hexane/diethyl ether (9/1) to give 495.2 mg of the title compound. MS (m/z): 156 (M+1).
Wird geladen…