[Cl:1][C:2]1[CH:7]=[C:6]([CH2:8][C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH:5]=[CH:4][N:3]=1.[CH3:14][Si]([N-][Si](C)(C)C)(C)C.[K+].CI.[NH4+].[Cl-]>C1COCC1.CCOCC>[Cl:1][C:2]1[CH:7]=[C:6]([CH:8]([CH3:14])[C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH:5]=[CH:4][N:3]=1
To a stirred solution of ethyl 2-(2-chloropyridin-4-yl)acetate (44) (2.5 g, 12.52 mmol) in THF (25 mL), under nitrogen at −78° C. was added a solution of KHMDS (0.5M in toluene, 26.3 mL, 13.2 mmol). The mixture was warmed to RT for 10 min, then re-cooled to −78° C. and methyl iodide (0.820 mL, 13.15 mmol) added in a single portion and the mixture allowed to warm to RT. Saturated aqueous NH4Cl solution was added and the mixture was diluted with ether. The organic layer was washed with water and brine and then dried (MgSO4) and evaporated in vacuo. The residue was purified by flash column chromatography (SiO2, 100 g, 5-10% EtOAc in isohexane, gradient elution) to afford the title compound (51) (1.57 g, 56%): m/z 214 (M+H)+ (ES+).
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