[Cl:1][C:2]1[C:11]([CH2:12][C:13]#[N:14])=[CH:10][CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].[H-].[Na+].Br[CH2:18][CH2:19][CH2:20]Br.O>CS(C)=O>[Cl:1][C:2]1[C:11]([C:12]2([C:13]#[N:14])[CH2:20][CH2:19][CH2:18]2)=[CH:10][CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5]A solution (15 mL) of methyl 2-chloro-3-(cyanomethyl)benzoate (1.50, 7.16 mmol) produced in Example C61(iii) in dimethylsulfoxide was cooled at which the solution did not solidify, sodium hydride (60%, 869 mg, 21.7 mmol) was slowly added, and the mixture was stirred at room temperature for 30 min. To the suspension was added dropwise 1,3-dibromopropane (1.45 mL, 14.3 mmol), and the mixture was stirred at room temperature for 1.5 hr. To the reaction mixture was slowly added water (50 mL), and the mixture was extracted with ethyl acetate (50 mL×3). The organic layer was washed successively with water (50 mL) and saturated brine (50 mL), dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=95/5→50/50) to give the title compound (714 mg, 40%) as a white powder.
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