4,4'-Dimethyl-2,2'-{[2,3,3a,4,5,6,7,7a-octa-hydro-1H-benzimidazole-1,3-di-yl]bis-(methyl-ene)}diphenol

The asymmetric unit of the title compound, C23H30N2O2, contains one half-mol-ecule, with a twofold axis splitting the mol-ecule in two identical halves. The structure of the racemic mixture has been reported previously [Rivera et al. (2009>) J. Chem. Crystallogr. 39, 827-830] but the enanti-omer reported here crystallized in the ortho-rhom-bic space group P21212 (Z = 2), whereas the racemate occurs in the triclinic space group P-1 (Z = 2). The observed mol-ecular conformation is stabilized by two intra-molecular O-H⋯N hydrogen bonds, which generate rings with graph-set motif S(6). In the crystal, mol-ecules are linked via non-classical C-H⋯O inter-actions, which stack the mol-ecules along the b axis

4,4′-Dibromo-2,2′-{[(3aS,7aS)-2,3,3a,4,5,6,7,7a-octa­hydro-1H-1,3-benzimidazole-1,3-di­yl]bis­(methyl­idene)}diphenol

The cyclo­hexane ring in the title compound, C21H24Br2N2O2, adopts a chair conformation and the five-membered ring to which it is fused has a twisted envelope conformation. The asymmetric unit contains one half-mol­ecule, which is related to the other half by a twofold rotation axis. The two N atoms of the five-membered ring are linked to the hy­droxy groups by intra­molecular O—H⋯N hydrogen bonds. In the crystal, inter­molecular C—H⋯O and C—H⋯π inter­actions occur

(1H-Benzimidazol-1-yl)methanol

In the title compound, C8H8N2O, the N—CH2 and CH2—O bond lengths can be correlated to the manifestation of an anomeric effect in the N—CH2—O moiety. In the crystal, inter­molecular O—H⋯N hydrogen bonds link the mol­ecules into zigzag chains, with graph-set motif C(6), parallel to [001]. These chains are further linked into sheets by weak nonclassical C—H⋯O hydrogen bonds

4,4′-Dichloro-3,3′,5,5′-tetra­methyl-2,2′-[(3aR,7aR/3aS,7aS)-2,3,3a,4,5,6,7,7a-octa­hydro-1H-1,3-benzimidazole-1,3-di­yl)bis­(methyl­ene)]diphenol

In the title compound, C25H32Cl2N2O2, there are two intra­molecular O—H⋯ N hydrogen-bonding inter­actions between the hy­droxy groups on the aromatic rings and the two N atoms of the heterocyclic group. The cyclo­hexane ring adopts a chair conformation and the imidazolidine unit to which it is fused has a twisted envelope conformation. The asymmetric unit comprises one half-mol­ecule which is completed by a twofold rotation axis. A C—H⋯O inter­action is observed in the crystal structure

3,3′-(Ethane-1,2-di­yl)bis­(6-methyl-3,4-dihydro-2H-1,3-benzoxazine)

The asymmetric unit of the title compound, C20H24N2O2, contains one half-mol­ecule, which is completed by inversion symmetry. In the crystal, mol­ecular chains are formed through non-classical C—H⋯O hydrogen bonds, formed between axial H atoms of the oxazine ring and a O atom of a neighboring mol­ecule

4,4′-Difluoro-2,2′-{[(3aRS,7aRS)-2,3,3a,4,5,6,7,7a-octa­hydro-1H-1,3-benzimidazole-1,3-di­yl]bis­(methyl­ene)]}diphenol

In the crystal structure of the title compound, C21H24F2N2O2, the two N atoms of the imidazolidine moiety are linked to the hy­droxy groups by intra­molecular O—H⋯N hydrogen-bonding inter­actions. The crystal studied was a racemic mixture of RR and SS enatiomers. The cyclo­hexane ring adopts a chair conformation and the imidazolidine group to which it is fused has a twisted envelope conformation

1-Heptyl-1,3,6,8-tetraaza­tricyclo­[4.3.1.13,8]undecan-1-ium iodide

The title compound C14H29N4 +·I− salt, was obtained by the reaction of cage adamanzane-type aminal 1,3,6,8-tetra­aza­tricyclo­[4.3.1.13,8]undecane with heptyl iodide. In the cation, the bond lengths and angles are within normal ranges, except for one N—C(ring) bond distance of 1.542 (3) Å, which is unexpectedly long compared with related compounds. In the crystal, ions are linked through C—H⋯I hydrogen bonds. The crystal studied was a non-merohedral twin with a minor twin domain of 6.56 (5)%

1-Hexyl-1,3,6,8-tetra­aza­tricyclo­[4.3.1.13,8]undecan-1-ium iodide

In the title compound, C13H27N4 +·I−, the ethyl­ene bridge is distorted from the ideal D 2d symmetry wherein an N—C—C—N planar bridge, around whose C—C bond the C—N and C—H bonds are exactly eclipsed, is disordered over two sites with equal occupancies. In both disorder components, the hexyl chain adopts an ideal all-trans conformation. In the crystal, adjacent ions are connected by C—H⋯I hydrogen bonds, forming ionic pairs that are further linked into chains along [101] via a second C—H⋯I inter­action

2,9-Dimethyl-6H,13H-5:12,7:14-dimethano­dibenzo[d,i][1,3,6,8]tetraazecine

In the title structure, C18H20N4, the aromatic rings are almost orthogonal [81.6 (2)°]. The mol­ecule has symmetry 2 since it is situated on a crystallographic twofold axis. There are only weak inter­molecular inter­actions present in the structure, notably C—H⋯π-electron ring inter­actions. The 1H and 13C NMR spectra are in accordance with the X-ray structure analysis

2,2′-[(3aRS,7aRS)-Perhydro­benz­imid­azole-1,3-di­yl)bis­(methyl­ene)]diphenol

The molecular structure of the title compound, C21H26N2O2, shows two intra­molecular O—H⋯N hydrogen-bonding inter­actions. In the crystal structure, mol­ecular chains are formed along the c axis through weak C—H⋯O inter­actions. Neighbouring chains are weakly associated along the a axis via C—H⋯π inter­actions