New diethoxo-bridged dinuclear Cr(III) complexes with derivatives of the quinoxaline-2,3-dione ligand and 2,2′-bipyridine as a co-ligand: Syntheses, spectral characterizations, magnetic properties, antimicrobial inhibitory activities and interpretation of the electronic absorption spectra using the ZINDO/S-CI semi-empirical method

The crystal structure of 7-Bromo-2-(4-chloro-phenyl)-quinoxaline, C14H9BrClN2

C14H8BrClN2, monoclinic, P21/n (no. 14), a = 17.1347(11) Å, b = 3.8441(2) Å, c = 18.4127(12) Å, β = 97.861(2)°, V = 1201.40(13) Å3, Z = 4, R gt (F) = 0.0388, wR ref (F 2) = 0.1302, T = 170 K.

Synthesis and crystal structure of (E)-1-benzyl-3-(4-methoxystyryl)quinoxalin-2(1H)-one, C24H20N2O2

C24H20N2O2, monoclinic, P21/c (no. 14), a = 11.1713(3) Å, b = 17.7718(5) Å, c = 10.9852(3) Å, β = 118.990(1)°, V = 1907.67(9) Å3, Z = 4, Rgt(F) = 0.0538, wRref(F2) = 0.1582, T = 296(2) K.

Crystal structure and Hirshfeld surface analysis of 1-[(1-butyl-1H-1,2,3-triazol-4-yl)meth-yl]-3-methyl-quinoxalin-2(1H)-one

The title compound, C16H19N5O, is built up from a planar quinoxalinone ring system linked through a methyl-ene bridge to a 1,2,3-triazole ring, which in turn carries an n-butyl substituent. The triazole ring is inclined by 67.09 (4)° to the quinoxalinone ring plane. In the crystal, the mol-ecules form oblique stacks along the a-axis direction through inter-molecular C-HTrz⋯NTrz (Trz = triazole) hydrogen bonds, and offset π-stacking inter-actions between quinoxalinone rings [centroid-centroid distance = 3.9107 (9) Å] and π-π inter-actions, which are associated pairwise by inversion-related C-HDhydqn⋯π(ring) (Dhydqn = di-hydro-quinoxaline) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (52.7%), H⋯N/N⋯H (18.9%) and H⋯C/C⋯H (17.0%) inter-actions.

Ethyl 2-(2-oxo-3-phenyl-1,2-dihydroquinoxalin-1-yl)acetate

In the title compound, C18H16N2O3, the dihydroquinoxaline moiety is planar (r.m.s. deviation = 0.0115 Å) and the majority of the ester substituent is nearly perpendicular to its mean plane. In the crystal, the molecules form oblique stacks along the b-axis direction through slipped π–π stacking interactions between adjacent dihydroquinoxaline units. C—H...O hydrogen bonds between the ester substituents on adjacent stacks form thick layers with the stacks on their outside surfaces. These layers extend along the c-axis direction and are coupled through C—H...π(ring) interactions. The structure was refined as a two-component twin.

1-(Prop-2-en-1-yl)-3-[(prop-2-en-1-yl)oxy]quinoxalin-2(1H)-one

In the title compound, C14H14N2O2, the dihydroquinoxaline moiety deviates slightly from planarity. In the crystal, zigzag chains are formed by inversion-related C—H...O hydrogen bonds. Adjacent chains are associated through pairwise C—H...π(ring) and π-stacking interactions.