C([Li])CCC.C(NC(C)C)(C)C.[C:13]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])(=[O:15])[CH3:14].[Br:21][C:22]1[CH:27]=[C:26]([Br:28])[N:25]=[C:24]([C:29]2[CH:34]=[CH:33][CH:32]=[CH:31][C:30]=2[Cl:35])[C:23]=1[CH2:36]Br>C1COCC1.C(O)(=O)C>[Br:21][C:22]1[CH:27]=[C:26]([Br:28])[N:25]=[C:24]([C:29]2[CH:34]=[CH:33][CH:32]=[CH:31][C:30]=2[Cl:35])[C:23]=1[CH2:36][CH2:14][C:13]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15]n-Butyllithium in hexanes (1.6 Molar (hereinafter “M”), 3.75 millilitre (hereinafter “ml”), 6.0 millimole (hereinafter “mmol”)) was added to di-isopropylamine (0.84 ml, 6.0 mmol) in dry THF (15 ml) at −10° under nitrogen. After 5 minutes (hereinafter “min”). the solution was cooled to −70° and tert-butyl acetate (0.5 ml, 3.71 mmol) added dropwise. After stirring at −70° C. for 10 min. under nitrogen, 4,6-Dibromo-3-(bromomethyl)-2-(2-chlorophenyl)pyridine (0.405 grams (hereinafter “g”), 0.92 mmol) in dry THF (15 ml) was added, and the mixture stirred at −70° for 2 h. Glacial acetic acid (2 ml) was added, the temperature allowed to rise to 22° and the solution evaporated in vacuo. The residue was purified by column chromatography over silica (50 g) eluting with cyclohexane-ethyl acetate (9:1)-(5:1) to give the product as an oil (0.21 g).
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