Hydrochloric Acid → 6-Fluoro-2-(piperidin-4-yl)-1H-benzimidazole

Reaction equation

[F:1][C:2]1[CH:23]=[CH:22][C:5]2[NH:6][C:7]([CH:9]3[CH2:14][CH2:13][N:12](C(OC(C)(C)C)=O)[CH2:11][CH2:10]3)=[N:8][C:4]=2[CH:3]=1.Cl>C(Cl)Cl.O1CCOCC1>[F:1][C:2]1[CH:23]=[CH:22][C:5]2[NH:6][C:7]([CH:9]3[CH2:10][CH2:11][NH:12][CH2:13][CH2:14]3)=[N:8][C:4]=2[CH:3]=1

Participants

Procedure

To a stirred solution of tert-butyl 4-(5-fluoro-1H-benzimidazol-2-yl)piperidine-1-carboxylate (0.81 g, 2.53 mmol) in DCM (8 mL) is added a solution of 4M HCl in dioxane (2 mL). The reaction mixture is stirred at room temperature for 18 h. The reaction mixture is concentrated under reduced pressure to give 0.74 g of 5-fluoro-2-(piperidin-4-yl)-1H-benzimidazole. This product is used in the next step without further purification.