2-Piperidin-4-yl-1H-benzimidazole is used as a reagent in the synthesis of 3-amino-1-(5-indanyloxy)-2-propanol derivatives as potent sodium channel blockers for the treatment of ischemic stroke. Also used as a reagent in the synthesis of 2,3,5-trisubstituted pyridine derivatives as potent Akt1/Akt2 dual inhibitors.
The general procedure for the synthesis of 2-(4-piperidinyl)-1H-benzimidazole from 4-piperidinecarboxylic acid and o-phenylenediamine was as follows: according to the method described in the literature (J. Heterocyclic Chem., 1989, 26, 54), benzene-1,2-diamine (12.6 g, 116 mmol) was mixed with piperidine-4-carboxylic acid (15 g, 116 mmol) in a 4M HCl aqueous solution (250 mL), stirred and heated under reflux conditions for 48 hours. Upon completion of the reaction, the mixture was cooled to room temperature and the pH was adjusted to alkaline with 5 M NaOH aqueous solution. The precipitate precipitated was collected by filtration, washed with water and subsequently dried in a vacuum oven to afford the target product 2-(piperidin-4-yl)-1H-benzimidazole 8.8 g in 38% yield. Mass spectrometry analysis showed m/z = 202 [M+ + H].
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[5] Patent: WO2010/80357, 2010, A1. Location in patent: Page/Page column 41-42
