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In the title compound, C26H24N2O2, the oxazine moiety is fused to a naphthalene ring system. The asymmetric unit consists of one half of the molecule, which lies about an inversion centre. The C atoms of the ethylene spacer group adopt an antiperiplanar arrangement. The oxazine ring adopts a half-chair conformation. In the crystal, supramolecular chains running along the b axis are formed via short C—H⋯π contacts. The crystal studied was a non-merohedral twin with a fractional contribution of 0.168 (2) of the minor twin component.
The asymmetric unit of the title compound, C28H42N2O5·H2O, consists of one half of the organic molecule and one half-molecule of water, both of which are located on a mirror plane which passes through the central C atoms and the hydroxyl group of the heterocyclic system. The hydroxyl group at the central ring is disordered over two equally occupied positions. The six-membered ring adopts a chair conformation, and the 2-hydroxybenzyl substituents occupy the sterically preferred equatorial positions. The aromatic rings make dihedral angles of 75.57 (9)° with the mean plane of the heterocyclic ring. The dihedral angle between the two aromatic rings is 19.18 (10)°. The molecular structure features two intramolecular phenolic O-H...N hydrogen bonds with graph-set motif S(6). In the crystal, molecules are connected via O-H...O hydrogen bonds into zigzag chains running along the a-axis direction.
In the title compound, C17H18N2O, the central carbon atom with the OH substituent and one of the (E)-benzylideneamino substituents are disordered over two sets of sites with occupancies of 0.851 (4) and 0.149 (4). The relative positions of the two disorder components is equivalent to a rotation of approximately 60° about the C—N single bond. In the crystal, the molecules are held together by O—H...N hydrogen bonds, forming simple C(5) chains along the b-axis direction. In addition, pairs of the chains are further aggregated by weak C—H...π interactions.
The asymmetric unit of the title compound, C21H28N4O, consists of two unique molecules linked by an O—H⋯N hydrogen bond. The conformation of both C=N bonds is E and the azomethine functional groups lie close to the plane of their associated benzene rings in each of the independent molecules. The dihedral angles between the two benzene rings are 83.14 (4) and 75.45 (4)°. The plane of the one of the N(CH3)2 units is twisted away from the benzene ring by 18.8 (2)°, indicating loss of conjugation between the lone electron pair and the benzene ring. In the crystal structure, O—H⋯N hydrogen bonds together with C—H⋯O hydrogen bonds link neighbouring supramolecular dimers into a three-dimensional network.
Crystal structure of 1,3-bis(3-tert-butyl-2-hydroxy-5-methylbenzyl)-1,3-diazinan-5-ol monohydrate
(2016)
In the title hydrate, C28H42N2O3·H2O, the central 1,3-diazinan-5-ol ring adopts a chair conformation with the two benzyl substituents equatorial and the lone pairs of the N atoms axial. The dihedral angle between the aromatic rings is 19.68 (38)°. There are two intramolecular O-H...N hydrogen bonds, each generating an S(6) ring motif. In the crystal, classical O-H...O hydrogen bonds connect the 1,3-diazinane and water molecules into columns extending along the b axis. The crystal structure was refined as a two-component twin with a fractional contribution to the minor domain of 0.0922 (18).
The title Schiff base, C19H22N2O3, was synthesized via the condensation reaction of 1,3-diaminopropan-2-ol with 4-methoxybenzaldehyde using water as solvent. The molecule exists in an E,E conformation with respect to the C=N imine bonds and the dihedral angle between the aromatic rings is 37.25 (15)°. In the crystal, O-H...N hydrogen bonds link the molecules into infinite C(5) chains propagating along the a-axis direction. The packing of these chains is consolidated by C-H...O interactions and C-H...[pi] short contacts, forming a three-dimensional network.
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.
In the title ternary co-crystalline adduct, C7H14N4·2C6H5NO3, molecules are linked by two intermolecular O—H⋯N hydrogen bonds, forming a tricomponent aggregates in the asymmetric unit. The hydrogen-bond formation to one of the N atoms is enough to induce structural stereoelectronic effects in the normal donor→acceptor direction. In the title adduct, the two independent nitrophenol molecules are essentially planar, with maximum deviations of 0.0157 (13) and 0.0039 (13) Å. The dihedral angles between the planes of the nitro group and the attached benzene rings are 4.04 (17) and 5.79 (17)°. In the crystal, aggregates are connected by C—H⋯O hydrogen bonds, forming a supramolecular dimer enclosing an R66(32) ring motif. Additional C—H⋯O intermolecular hydrogen-bonding interactions form a second supramolecular inversion dimer with an R22(10) motif. These units are linked via C—H⋯O and C—H⋯N hydrogen bonds, forming a three-dimensional network.
The title compound, C23H32Cl2N2O2, a potential chiral ligand for coordination chemistry, was prepared by a two-step reaction. The molecule is located on a crystallographic centre of inversion. As a result, the methyl group bonded to the methylene group is disordered over two equally occupied positions, sharing the same site as the H atom of the chiral C atom. As a further consequence of the crystallographic centrosymmetry, the 1,2-diaminopropane unit adopts an antiperiplanar conformation and the two benzene rings are coplanar. The central chain is in an all-trans arrangement. An intramolecular O-H...N hydrogen bond makes an S(6) ring motif. A C-H...[pi] interaction links the molecules into one-dimensional chains along the [001] direction.
In the title compound, C7H14N4·2C6H5ClO, which crystallized with two crystallographically independent 4-chlorophenol molecules and one 1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecane (TATU) molecule in the asymmetric unit, the independent components are linked by two O-H...N hydrogen bonds. The hydrogen-bond acceptor sites are two non-equivalent N atoms from the aminal cage structure, and the tricyclic system distorts by changing the C-N bond lengths. In the crystal, these hydrogen-bonded aggregates are linked into chains along the c axis by C-H...N hydrogen bonds. The crystal structure also features C-H...[pi] contacts.