Process and intermediates for obtaining 1-(1H-benzimidazol-2-YL)-4-(2-aminopyrimidine)piperidine derivatives

摘要

A method is provided for obtaining derivatives of 1-(1H-Benzimidazole-2-il)-4-(2-aminopyrimidine)piperidine (IV), wherein R₁ represents hydrogen or 4-halobenzul and R₅ represents optionally-substituted hydrogen, alkyl or benzyl. The method includes the conversion of a 1-[1-(R₁)-1-(1H-Benzimidazole-2-il)-4-(R₂)(R₃)-piperidine (I), wherein R₂ or R₃ represents optionally-protected hydroxyl, or R₂ and R₃ represent, independently of each other, optionally-substituted alkoxy or benzyloxy, or R₂ and R₃ together form an optionally-substituted alkylenedioxy group, by hydrolysis and/or oxidation into a 1-[1-(R₁)-1-(1H-Benzimidazole-2-il)-4-piperidone, which, by reductive amination (with optional separation of the intermediate imina formed) provides the corresponding amine which, by reaction with a pyrimidine, produces the above-mentioned derivative of 1-(1H-Benzimidazole-2-il)-4-(2-aminopyrimidine) piperidine (IV).