Thiophene → (1H-Benzoimidazol-2-yl)-(1-methyl-piperidin-4-yl)-amine

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Reaction Steps

A mixture of 36.6 parts of N-(4-piperidinyl)-1H-benzimidazol-2-amine dihydrobromide, 10 parts of poly(oxymethylene), 2 parts of a solution of thiophene in methanol 4%, 200 parts of methanol and 20 parts of potassium hydroxide was hydrogenated at normal pressure and at room temperature with 4 parts of palladium-on-charcoal catalyst 10%. After the calculated amount of hydrogen was taken up, the catalyst was filtered off and the filtrate was evaporated. The residue was treated with a sodium hydroxide solution. The precipitated product was filtered off and dried, yielding 13.7 parts (59.4%) of N-(1-methyl-4-piperidinyl)-1H-benzimidazol-2-amine (interm 30).

Provenance & Evidence