2-(1H-Benzimidazol-2-yl)phenol.

The title mol-ecule, C13H10N2O, is essentially planar, the maximum deviation from the plane of the non-H atoms being 0.016 (2) Å. The imidazole ring makes a dihedral angle of 0.37 (13)° with the attached benzene ring. An intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked through N-H⋯O hydrogen bonds, forming chains propagating in [001]. The crystal packing also features four π-π stacking inter-actions involving the imidazole ring, fused benzene ring and attached benzene ring system [centroid-centroid distances = 3.6106 (17), 3.6108 (17), 3.6666 (17) and 3.6668 (17) Å].

2-(Naphthalen-1-yl)-1-phenyl-1H-benzimid-azole benzene hemisolvate.

In the title compound, C23H16N2·0.5C6H6, the benzimidazole unit [maximum deviation = 0.0258 (6) Å] and the naphthalene ring system [maximum deviation = 0.0254 (6) Å] are both essentially planar and make a dihedral angle of 61.955 (17)°. The imidazole ring makes dihedral angle of 61.73 (4)° with the phenyl ring. An intra-molecular C-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, seven weak C-H⋯π inter-actions involving the fused ring system, the benzene solvent mol-ecule, the imidazole phenyl rings are observed, leading to a three-dimensional architecture.

2-(1-Phenyl-1H-benzimidazol-2-yl)phenol.

In the title mol-ecule, C19H14N2O, the benzimidazole unit is close to being planar [maximum deviation = 0.0253 (11) Å] and forms dihedral angles of 68.98 (6) and 20.38 (7)° with the adjacent phenyl and benzene rings; the dihedral angle between the latter two planes is 64.30 (7)°. An intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked by C-H⋯N and C-H⋯O hydrogen bonds, and consolidated into a three-dimensional architecture by π-π stacking inter-actions, with a centroid-centroid distance of 3.8428 (12) Å.

2-(4-Fluoro-phen-yl)-1-phenyl-1H-benzimidazole.

In the title mol-ecule, C(19)H(13)FN(2), the benzimidazole unit is close to planar [maximum deviation = 0.0342 (9) Å] and forms dihedral angles of 58.94 (3) and 51.43 (3)° with the phenyl and fluoro-benzene rings, respectively; the dihedral angle between the phenyl and fluoro-benzene rings is 60.17 (6)°. In the crystal, three C-H⋯F hydrogen bonds and two weak C-H⋯π inter-actions involving the fused benzene ring lead to a three-dimensional architecture.

1-(3,5-Dimeth-oxy-phen-yl)-2-(4-fluoro-phen-yl)-4,5-dimethyl-1H-imidazole.

In the title compound, C(19)H(19)FN(2)O(2), the imidazole ring is essentially planar [maximum deviation = 0.0030 (8) Å] and makes dihedral angles of 66.45 (7) and 29.98 (7)° with the benzene rings attached to the ring N and C atoms, respectively. The dihedral angle between the two benzene rings is 64.79 (7)°. A C-H⋯π inter-action is found in the crystal structure. The two meth-oxy groups were found to be disordered over two sets of sites with occupancy factors of 0.803 (4) and 0.197 (4). The F atom is disordered over two sites with occupancy factors of 0.929 (4) and 0.071 (4).

2-(4-Fluoro-phen-yl)-1-(4-methyl-phen-yl)-1H-phenanthro[9,10-d]imidazole.

The phenanthrene tricyclic ring system in the title mol-ecule, C(28)H(19)FN(2), is slightly skewed with a dihedral angle of 7.50 (6)° between the outer benzene rings. The p-tolyl and fluoro-benzene rings are twisted from the attached imidazole ring by 70.40 (7) and 28.33 (7)°, respectively. In the crystal, C-H⋯F hydrogen bonds link the mol-ecules into zigzag chains in [001], and weak C-H⋯π inter-actions further consolidate the crystal packing.

1,2-Diphenyl-1H-benzimidazole.

In the title mol-ecule, C19H14N2, the benzimidazole unit is close to being planar [maximum deviation = 0.0102 (6) Å] and forms dihedral angles of 55.80 (2) and 40.67 (3)° with the adjacent phenyl rings; the dihedral angle between the phenyl rings is 62.37 (3)°. In the crystal, one C-H⋯N hydrogen bond and three weak C-H⋯π inter-actions involving the fused benzene ring and the imidazole ring are observed, leading to a three-dimensional architecture.

1-(4-Methyl-benz-yl)-2-(4-methyl-phen-yl)-1H-benzimidazole.

The title compound, C(22)H(20)N(2), crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. The benzimidazole units are almost planar [maximum deviations = 0.0161 (8) Šfor A and 0.0276 (8) Šfor B]. The dihedral angles between the benzimidazole unit and the benzene rings of the 4-methyl-benzyl and 4-methyl-phenyl groups are 76.64 (3) and 46.87 (4)°, respectively, in mol-ecule A. The corresponding values in mol-ecule B are 86.31 (2) and 39.14 (4)°. The dihedral angles between the planes of the two benzene rings are 73.73 (3) and 80.69 (4)° in mol-ecules A and B, respectively. Pairs of weak inter-molecular C-H⋯N hydrogen bonds link B mol-ecules, forming centrosymmetric dimers with R(2) (2)(8) ring motifs. There are no significant corresponding inter-actions involving the A mol-ecules.

2-(4-Fluoro-phen-yl)-1-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline monohydrate.

In the title compound, C(25)H(15)FN(4)·H(2)O, the fused ring system is essentially planar [maximum deviation of 0.0822 (14) Å]. The imidazole ring makes dihedral angles of 76.83 (7) and 32.22 (7)° with the phenyl group attached to nitro-gen and the fluoro-benzene group to carbon, respectively. The dihedral angle between the two phenyl rings is 72.13 (7)°. Inter-molecular O-H⋯N, O-H⋯F, C-H⋯F, C-H⋯O and C-H⋯N hydrogen bonds are found in the crystal structure.

1,2-Diphenyl-1H-imidazo[4,5-f][1,10]phenanthroline.

In the title compound, C(25)H(16)N(4), the fused ring system is essentially planar [maximum deviation = 0.1012 (15) Å]. The imidazole ring makes dihedral angles of 77.41 (8) and 56.26 (8)° with the phenyl rings attached to nitro-gen and carbon, respectively. The dihedral angle between the two phenyl rings is 65.50 (8)°. Weak C-H⋯π inter-actions are found in the crystal structure.

1-(3,5-Dimethyl-phenyl)-2-(4-fluoro-phenyl)-4,5-dimethyl-1H-imidazole.

In the title compound, C(19)H(19)FN(2), the imidazole ring is essentially planar [maximum deviation of 0.0015 (9) Å] and makes dihedral angles of 77.61 (9) and 26.93 (10)° with the benzene rings attached to nitro-gen and carbon, respectively. The dihedral angle between the two benzene rings is 78.84 (8)°. A C-H⋯π inter-action is found in the crystal structure.