Syntheses and crystal structures of versatile supramolecular reagents based upon [(benzimidazol-1-yl)methyl]-benzamides

A new family of supramolecular reagents based upon [(benzimidazol-1-yl)methyl]-benzamides and geared toward the assembly of binary and ternary cocrystals have been synthesized and characterized. Single-crystal structure determinations of four of these compounds demonstrate that the carboxamide moieties engage in either dimeric or catemeric self-complementary hydrogen bonds, as well as in a N-H (...) N hydrogen bond involving the anti proton of the amide moiety (the hydrogen-bond donor) and a heterocyclic nitrogen atom (the hydrogen-bond acceptor). The crystal structures of two binary cocrystals illustrate that [(benzimidazol-1-yl)methyl]-benzamides are capable of coexisting within a crystalline lattice with a suitable partner, and this fact, coupled with their wide ranging solubility, makes them into versatile and, potentially, very useful supramolecular reagents.