1-Hexyl-1,3,6,8-tetra­aza­tricyclo­[4.3.1.1^3,8]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.

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

The title compound, C₁₈H₂₀N₂O₂, was prepared by Mannich-type reaction of phenol, ethane-1,2-diamine and formaldehyde. The heterocyclic rings adopt half-chair conformations. The acyclic methyl­ene groups attached to the N atoms are in an axial position. In the crystal, weak C—H...O hydrogen bonds link the mol­ecules into dimers. These dimers are further connected via C—H...π contacts.

2,2′-[Imidazolidine-1,3-diylbis(methyl­ene)]diphenol

In the title mol­ecule, C₁₇H₂₀N₂O₂, the imidazolidine ring adopts a twist conformation. The mean plane through the five atoms of the imidazolidine ring makes dihedral angles of 70.18 (4) and 74.14 (4)° with the planes of the two aromatic rings. The dihedral angle between the benzene rings is 53.11 (5)°. Both phenol –OH groups form intra­molecular hydrogen bonds to the N atoms, with graph-set motif S(6). In the crystal, pairs of O—H...O hydrogen bonds link the mol­ecules into dimers with R₄⁴(18) ring motifs. The crystal packing is further stabilized by C—H...O and weak C—H...π inter­actions.

6,6′-Di-tert-butyl-4,4′-dimeth­oxy-2,2′-[1,3-diazinane-1,3-diylbis(methyl­ene)]diphenol 0.19-hydrate

In the title hexa­hydro­pyrimidine derivative, C₂₈H₄₂N₂O₄·0.19H₂O, the 1,3-diazinane ring has a chair conformation with a diequatorial substitution. The asymmetric unit contains one half-organic mol­ecule and a solvent water mol­ecule with occupany 0.095. The mol­ecule lies on a mirror plane perpendicular to [010] which passes through the C atoms at the 2- and 5-positions of the heterocyclic system. The partially occupied water mol­ecule is also located on this mirror plane. The dihedral angle between the planes of the aromatic rings is 17.71 (3)°. Two intra­molecular O—H...N hydrogen bonds with graph-set motif S(6) are present. No remarkable inter­molecular contacts exist in the crystal structure.