This chapter describes the X-ray crystal structure analysis of selected benzimidazole derivatives, viz. BIP: 2-(1H-benzimidazol-2-yl)phenol, MBMPBI: 1-(4-methylbenzyl)-2-(4-methylphenyl)-1H-benzimidazole, DPBI: 1,2-diphenyl-1H-benzimidazole, PBIP: 2-(1-phenyl-1H-benzimidazol-2-yl)phenol, FPPBI: 2-(4-fluorophenyl)-1-phenyl-1H-benzimidazole and NPBIBHS: 2-(naphthalen-1-yl)-1-phenyl-1H-benzimidazole benzene hemisolvate. The BIP molecule is planar, and in the crystal, it is arranged in parallel planes, stabilised by π-π interactions and the hydrogen bonds. In MBMPBI, benzimidazole cores of the two independent (A and B) molecules are planar. Two C▬H…N hydrogen bonds link B molecules only, forming centrosymmetric dimers with R22(8) ring motifs. In the DPBI molecule, the benzimidazole core is planar: one hydrogen-bond interaction (C▬H…N) and C▬H…π (three) interaction leading to the three-dimensional arrangement. In the PBIP molecule, the benzimidazole is nearly planar. The hydrogen bonds and a π-π stacking interaction are present in the crystal. In the FPPBI molecule, the benzimidazole unit is almost planar. The C▬H…F hydrogen bonds and weak C▬H…π interactions lead to a three-dimensional architecture in the crystal. In NPBIBHS, the naphthalene fragment lies out of the plane about the benzimidazole core unit. The C▬H…N hydrogen bonds and C▬H…π interactions lead to a three-dimensional architecture in the crystal.
Part of the book: Chemistry and Applications of Benzimidazole and its Derivatives