[Cl:1][C:2]1[N:6]([CH2:7][C:8](OC(C)C)=[O:9])[C:5]2[C:14]([CH:19]([CH2:22][CH3:23])[CH2:20][CH3:21])=[CH:15][CH:16]=[C:17]([Cl:18])[C:4]=2[N:3]=1.[BH4-].[Li+]>O1CCCC1>[Cl:1][C:2]1[N:6]([CH2:7][CH2:8][OH:9])[C:5]2[C:14]([CH:19]([CH2:22][CH3:23])[CH2:20][CH3:21])=[CH:15][CH:16]=[C:17]([Cl:18])[C:4]=2[N:3]=1To a solution of isopropyl [2,4-dichloro-7-(1-ethylpropyl)-1H-benzimidazol-1-yl]acetate (2.06 g, 5.773 mmol) in tetrahydrofuran (15.0 mL) was added lithium tetrahydroborate (377.2 mg, 17.318 mmol) at 0° C. The reaction mixture was stirred at 60° C. for 1 hr. After cooling, the reaction mixture was quenched with water at 0° C. and extracted with ethyl acetate (×3). The combined organic layer was washed with brine (×1), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with a 0-35% ethyl acetate/n-hexane gradient mixture to give the title compound as a colorless solid (883.0 mg, 2.932 mmol, 51%).
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