1-(4-Hydroxyphenyl)-2-(2-oxidonaphthalen-1-yl)diazen-1-ium methanol hemisolvate

In the title compound, C16H12N2O2·0.5CH3OH, the H atom of the –OH group has been transfered to the N atom in the azo group, forming a zwitterion. Hence, there is an intramolecular N—H...O, rather than an O—H...N, hydrogen bond in the molecule. The molecule is almost planar, the dihedral angle between the benzene ring and the mean plane of the naphthalene ring system being 4.51 (6)°. In the crystal, molecules are linked to and bridged by O—H...O hydrogen bonds involving the methanol molecule, which is located about a twofold rotation axis, and hence half-occupied, forming zigzag chains along [001]. Molecules are also linked via C—H...π and π–π interactions, the latter involving adjacent benzene and naphthalene rings and having a centroid–centroid distance of 3.6616 (13) Å, forming a three-dimensional network

1-[(E)-2-(2-Hydroxy-5-methylphenyl)diazen-2-ium-1-yl]naphthalen-2-olate

The title zwitterion, C17H14N2O2, crystallizes with two independent molecules in the asymmetric unit, both of which are approximately planar, the dihedral angles between the benzene ring and the naphthalene ring system being 4.39 (12)° in one molecule and 5.83 (12)° in the other, and show an E conformation with respect to the azo double bond. An intramolecular N—H...O hydrogen bond in each molecule helps to establish their near planar conformation. In the crystal, molecules are linked through O—H...O hydrogen bonds into infinite chains running along the a-axis direction. In addition, the chains are stacked along the b axis via π–π interactions between the benzene and the naphthalene rings of adjacent molecules, the centroid–centroid distances being 3.722 (3) and 3.823 (4) Å

(E)-1-(4-Fluorophenyl)-2-(2-oxidonaphthalen-1-yl)diazen-1-ium

In the title zwitterion, C16H11FN2O, which belongs to the family of azo dyes, the dihedral angle between the benzene ring and the naphthalene ring system is 15.33 (7)° and an intramolecular N—H...O hydrogen bond closes an S(6) ring. In the crystal, inversion dimers linked by weak C—H...O hydrogen bonds generate R22(16) loops. Aromatic π–π stacking [centroid–centroid distance = 3.585 (11) Å] is also observed

(E)-1-[(2,4,6-Tribromophenyl)diazenyl]naphthalen-2-ol

The title azo molecule, C16H9Br3N2O, adopts a trans conformation with respect to the azo N=N double bond. An intramolecular O—H...N hydrogen bond forms an S(6) ring motif. The dihedral angle between the naphthalene ring system and the benzene ring is 33.80 (16)°. In the crystal, molecules are stacked in columns along the a axis by π–π interactions [centroid–centroid distances = 3.815 (3) and 3.990 (3) Å]

cis-Dichlorido[4,4,5,5-tetramethyl-2-(2-pyridyl)-2-imidazoline-1-oxyl]palladium(II) tetrahydrofuran hemisolvate

The asymmetric unit of the title complex, [PdCl2(C12H16N3O)]·0.5C4H8O, consists of one palladium complex in a general position and one half tetrahydrofuran (THF) solvent molecule, with the O atom lying on a twofold rotation axis. The PdII atom is bound to one chelating imino nitroxide radical through two N atoms, one from the pyridyl ring and the other from the imidazoline ring. The coordination of the metal centre is completed by two Cl atoms in a cis configuration, leading to a quasi-square-planar coordination of the metal centre. The four atoms that define the PdII coordination environment and the eight atoms that belong to the pyridylimine fragment are coplanar, with no deviation larger than 0.087 (5) Å. In the crystal structure, intermolecular interactions shorter than the corresponding van der Waals radii sum are observed only between PdII complexes, and no short contact is observed around the THF molecule. Weak C—H...O and C—H...Cl interactions yield a two-dimensional network of complexes in the (101) plane

(E)-1-(3-Formylphenyl)-2-(2-oxidonaphthalen-1-yl)diazen-1-ium

In the title zwitterion, C17H12N2O2, the dihedral angle between the benzene ring and naphthalene ring system is 11.76 (7)° and an intramolecular N—H...O hydrogen bond exists. In the crystal, molecules are linked via pairs of C—H...O hydrogen bonds, forming inversion dimers

Crystal structure of bis{1-[(E)-(2-methoxyphenyl)diazenyl]naphthalen-2-olato-κ3O,N2,O′}copper(II) containing an unknown solvate

The title complex, [Cu(C17H13N2O2)2], crystallizes with two independent molecules in the asymmetric unit. Each CuII atom has a distorted ocahedral coordination environment defined by two N atoms and four O atoms from two tridentate 1-[(E)-(2-methoxyphenyl)diazenyl]naphthalen-2-olate ligands. In the crystal, the two molecules are linked via weak C—H...O hydrogen bonds which in turn stack parallel to [010]. A region of disordered electron density, most probably disordered methanol solvent molecules, was corrected for using the SQUEEZE routine in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. Their formula mass and unit-cell characteristics were not taken into account during refinement