[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([CH:24]=[O:25])=[C:6]2[C:10]=1[N:9]=[C:8]1[N:11]([C:15]3[C:20]([CH3:21])=[CH:19][C:18]([Cl:22])=[CH:17][C:16]=3[Cl:23])[CH2:12][CH2:13][CH2:14][N:7]21.[CH2:26]([Mg]Br)[CH2:27][CH:28]=[CH2:29]>O1CCCC1.[Cl-].[NH4+]>[Cl:1][C:2]1[C:10]2[N:9]=[C:8]3[N:11]([C:15]4[C:20]([CH3:21])=[CH:19][C:18]([Cl:22])=[CH:17][C:16]=4[Cl:23])[CH2:12][CH2:13][CH2:14][N:7]3[C:6]=2[C:5]([CH:24]([OH:25])[CH2:29][CH2:28][CH:27]=[CH2:26])=[CH:4][CH:3]=1To a suspension of 9-chloro-1-(2,4-dichloro-6-methylphenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole-6-carbaldehyde (150 mg, 0.380 mmol) in tetrahydrofuran (3.8 mL) was added dropwise 3-butenylmagnesium bromide (ca. 0.8 M solution in diethyl ether, 0.900 mL) at 0° C., and the mixture was stirred at room temperature for 30 min. The reaction mixture was diluted with aqueous saturated ammonium chloride, and extracted with ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture to give the two title compounds as colorless solids.
Loading…