[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][N:9]=2)=[CH:4][CH:3]=1.[CH2:14](I)[CH3:15].[BH4-].[Na+]>CN(C=O)C.CO>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH:8]2[CH2:13][CH:12]=[CH:11][CH2:10][N:9]2[CH2:14][CH3:15])=[CH:6][CH:7]=1To a solution of 2-(4-bromophenyl)pyridine (2.7 g, 11.5 mmol) in DMF (50 mL) was added ethyl iodide (1.9 mL, 23.1 mmol) and the reaction mixture was heated to 80° C. for 16 h. The mixture was cooled then evaporated and the resultant residue dissolved in methanol (100 mL) before addition of sodium borohydride (1.5 g, 39.2 mmol) portionwise. The reaction mixture was stirred at ambient temperature for 1 h then evaporated and saturated aqueous sodium carbonate solution was added. The mixture was extracted with ethyl acetate (2×100 mL). The combined organic layer was dried over sodium sulfate, filtered and evaporated then the residue was purified by flash chromatography (silica, Biotage 100 g column, 50% ethyl acetate in cyclohexane) to afford the title compound (0.9 g, 29%), which was used without further purification. 1H NMR (CDCl3, 300 MHz): 7.47-7.42 (m, 2H), 7.24-7.19 (m, 2H), 5.86-5.74 (m, 2H), 3.47-3.35 (m, 2H), 2.98-2.87 (m, 1H), 2.64-2.46 (m, 1H), 2.33-2.26 (m, 2H), 2.13-2.00 (m, 1H), 0.99 (t, J=7.2 Hz, 3H).
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