[CH3:1][C:2]1[CH:7]=[CH:6][N:5]=[CH:4][CH:3]=1.[Cl:8][C:9]1[S:13][C:12]([C:14](OCC)=[O:15])=[CH:11][CH:10]=1.C[Si]([N-][Si](C)(C)C)(C)C.[Li+]>C1COCC1>[Cl:8][C:9]1[S:13][C:12]([C:14](=[O:15])[CH2:1][C:2]2[CH:7]=[CH:6][N:5]=[CH:4][CH:3]=2)=[CH:11][CH:10]=1To a solution of 4-methylpyridine (32.3 mmol) and ethyl 5-chlorothiophene-2-carboxylate (35.5 mmol) in anhydrous THF (58 mL) at 0° C., under N2 was added dropwise a solution of lithium bis(trimethylsilyl)amide (1 molar solution in hexanes, 64.5 mmol). The mixture was stirred 3 h at 5° C. The resulting precipitate was filtered and acidified with 6 molar HCl. The precipitate was then filtered and dried to afford 2.9 g (35% yield) of 1-(5-chloro-2-thienyl)-2-(pyridin-4-yl)ethanone.
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