Yang-Hui Luo

Aqua­[bis­(2-ethyl-5-methyl-1H-imidazol-4-yl-κN3)methane]­oxalatocopper(II) dihydrate

In the title compound, [Cu(C2O4)(C13H20N4)(H2O)]·2H2O, the CuII atom exhibits a distorted square-pyramidal geometry with the two N atoms of the imidazole ligand and the two O atoms of the oxalate ligand forming the basal plane, while the O atom of the coordinated water molecule is in an apical position. The CuII atom is shifted 0.232 (2) Å out of the basal plane toward the water molecule. The asymmetric unit is completed by two solvent water molecules. These water molecules participate in the formation of an intricate three-dimensionnal network of hydrogen bonds involving the coordinated water molecule and the NH groups.

4-Nitro­isophthalic acid

In the crystal structure of the title compound, C8H5NO6, both carboxyl groups are involved in intermolecular centrosymmetric cyclic O—H⋯O hydrogen-bonding associations, which give a zigzag chain structure extending along (21). Weak π–π stacking interactions are also present [minimum ring centroid separation = 3.893 (4) Å].

2,4-Dibromo-6-[(hydroxyimino)methyl]phenol.

In the title compound, C7H5Br4NO2, intramolecular O—H⋯N hydrogen bonds are observed. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules into dimers.

2-(7-Methyl-1H-indol-3-yl)acetonitrile

In the title compound, C11H10N2, the carbonitrile group is twisted away from the indole plane [Ccy—Cme—Car—Car = 66.6 (2)°; cy = cyanide, me = methylene and ar = aromatic]. In the crystal, N—H⋯N hydrogen bonds link the molecules into C(7) chains propagating in the [001] direction.

6-Methyl­nicotinic acid

All non-H atoms of the title compound, C7H7NO2, are nearly coplaner, the r.m.s. deviation being 0.0087 Å. In the crystal, the partially overlapped arrangement and the face-to-face distance of 3.466 (17) Å between parallel pyridine rings of neighboring molecules indicates the existence of π–π stacking. Intermolecular O—H⋯N hydrogen bonding and weak C—H⋯O hydrogen bonding are present in the crystal structure.

2-(4-Chloro-1H-indol-3-yl)acetonitrile

The title compound, C10H7ClN2, contains two approximately planar molecules, A and B (r.m.s. deviations = 0.039 and 0.064 Å, respectively) in the asymmetric unit. In the crystal, N—H⋯N hydrogen bonds link the molecules into C(7) chains of alternating A and B molecules propagating along the a-axis direction. The crystal used for the data collection was found to be a racemic twin.

5-Chloro-1H-indole-3-carb­oxy­lic acid

In the title compound, C9H6ClNO2, the carboxyl group is twisted from the indole ring system by 9.00 (8)°. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds generate R 2 2(8) loops and N—H⋯O hydrogen bonds link the dimers into (001) sheets. Aromatic π–π stacking interactions [centroid–centroid distance = 3.7185 (12) A °] are also observed.

6-Chloro-quinolin-2(1H)-one.

In the title compound, C9H6ClNO, the Cl atom deviates by 0.142 (1) Å from the quinoline ring mean plane (r.m.s. deviation = 0.013 Å). In the crystal, N—H⋯O hydrogen bonds link the molecules into [010] C(4) chains. Aromatic π–π stacking interactions [shortest centroid⋯centroid distance = 3.685 (3) Å] are also observed.

(5-Meth­oxy-1H-indol-3-yl)acetonitrile

In the title compound, C11H10N2O, the O atom and the C atom of the methylene group deviate only slightly [0.029 (3) and 0.055 (3) Å, respectively] from the approximately planar ring system (r.m.s. deviation = 0.013 Å). In the crystal, N—H⋯O hydrogen bonds link the molecules into zigzag chains running along the b axis.

Dichlorido[bis-(2-ethyl-5-methyl-1H-imidazol-4-yl-κN)methane]-cobalt(II) monohydrate.

In the title compound, [CoCl2(C13H20N4)]·H2O, the CoII atom lies on a mirror plane and is four-coordinated by two N atoms of the imidazole ligand and two Cl atoms in a distorted tetrahedral arrangement. The water molecule participates in the formation of hydrogen bonds, resulting in a three dimensional network involving the Cl atoms and the NH groups. The terminal C atom of the ethyl group is disordered over two sites of equal occupancy.