Synthesis of N-Boc-Protected Bis(2-benzimidazolylmethyl)amines

摘要

Preparation of bis(1-tert-butoxycarbonyl-2-benzimida-zolylmethyl)amines from N-tert-butoxycarbonyl-protected 2-chlo-romethylbenzimidazole is described. The reaction with primaryamines containing several functional groups afforded bis(1-tert-butoxycarbonyl-2-benzimidazolylmethyl)amines in good yields.Hydrogenolysis of bis(2-benzimidazolylmethyl)benzylamine, cata-lyzed by Pd(OH)_2/C, cleaved the benzyl group, leaving thetent-butoxycarbonyl and 2-benzimidazolylmethyl groups intact. Theproduct of the latter reaction, bis(1-tert-butoxycarbonyl-2-benzimi-dazolylmethyl)amine, was thus obtained in 56% yield; the presenceof the tert-butoxycarbonyl groups at the N-benzimidazole positionsmakes it amenable to further functionalization at the central nitro-gen atom.