Synthesis, Characterization, Photophysical And Computational Study Of Schiff Base Ligands And Their Zn(II) Complexes [QD1-999].

Ligan bes Schiff dan kompleks Zn(II)nya telah menunjukkan kebolehan yang baik untuk pelbagai aplikasi disebabkan sifat-sifat dalam keadaan asas dan terujanya yang menarik. Schiff base ligands and their Zn(II) complexes have shown good potentials in a range of applications due to their interesting ground and excited state properties

Crystal structure of 4-methyl-N-[(4-methylpyridin-2-yl) carbamothioyl]benzamide

The authors would like to thank Universiti Sains Malaysia for a research grant (PKIMIA 846017), which partially supported this work.Peer reviewedPublisher PD

Manganese(III) Complexes with Tetradentate Schiff Base Ligands: IR, UV/Vis, Electrochemistry and Fluorescence Properties

Three trivalent manganese complexes have been synthesized, isolated, and characterized, namely, [MnCl(OH2)(Lx)].nH2O (I-III). Lx is a tetradentate Shiff base ligand, where Lx = LI, 2,2'-{1,2-phenylenebis [nitrilomethylylidene]}bis(phenolate), LII, 2,2'-{1,2-phenylenebis[nitrilomethylylidene]}bis(5-methoxyphenolate), and LIII, 2,2'-{1,2-phenylenebis[nitrilomethylylidene]}bis(4-methoxyphenolate), n = 1, 1.5 and 0 for I, II and III, respectively. These complexes were characterized using IR, elemental analysis and UV-Vis spectroscopy. In addition, the fluorescence, photoluminescence (PL), electrochemistry and thermal stability of these complexes were studied

2-(5,6-Dihydro­benzimidazo[1,2-c]quinazolin-6-yl)-6-eth­oxy­phenol

In the title compound, C22H19N3O2, the phenol ring forms dihedral angles of 88.93 (10) and 87.95 (12)° with the benzimidazole system and the quinazoline benzene ring, respectively. In the crystal, mol­ecules are linked via O—H⋯N hydrogen bonds into infinite chains along [100]. An intra­molecular N—H⋯O hydrogen bond generates an S(6) ring

4-(5,6-Dihydro­benzimidazo[1,2-c]quinazolin-6-yl)benzene-1,3-diol dimethyl sulfoxide monosolvate

In the title solvated benzimidazole compound, C20H15N3O2·C2H6OS, both the benzimidazole fused-ring system and the complete dimethyl sulfoxide solvent mol­ecule are disordered over two sets of sites, in 0.750 (5):0.250 (5) and 0.882 (4):0.118 (4) ratios, respectively. The conformation of the pyrimidine ring is close to a half-chair for the major disorder component, whereas for the minor component it is close to a boat. The dihy­droxy­phenyl ring is almost perpendicular to the mean plane of the benzimidazole ring [dihedral angle = 87.3 (2)° for the major disorder component and 88.3 (5)° for the minor disorder component]. In the crystal, mol­ecules are linked into layers parallel to (110) by O—H⋯N and C—H⋯O hydrogen bonds. A bifurcated O—H⋯(O,S) bond links the benzimidazole and solvent mol­ecules

2-(5,6-Dihydro­benzimidazo[1,2-c]quinazolin-6-yl)-5-methyl­phenol

In the title compound, C21H17N3O, the imidazole ring is essentially planar, with a maximum deviation of 0.009 (1) Å. The mol­ecule is disordered over two sites corresponding to a rotation of approximately 180° with a refined occupancy ratio of 0.9180 (14):0.0820 (14). The central pyrim­idine ring makes dihedral angles of 5.02 (5), 3.97 (5) and 6.28 (5)°, respectively, with the planes of the imidazole and the terminal phenyl rings for the major component; the values for the minor component are 5.8 (7), 5.0 (6) and 8.5 (6)°, respectively. Part of the observed planarity is accounted for in terms of an intra­molecular N—H⋯O hydrogen bond. In the crystal, mol­ecules of the major component are connected by O—H⋯N hydrogen bonds, forming supra­molecular chains along the c axis

[2-(1H-Benzimidazol-2-yl-κN 3)aniline-κN]dichloridozinc

In the title benzimidazole mononuclear complex, [ZnCl2(C13H11N3)], the ZnII ion is four-coordinated in a distorted tetra­hedral geometry by an imidazole N, an amino N and two Cl atoms. The dihedral angle between the benzimidazole and benzene rings is 9.57 (1)°. In the crystal, mol­ecules are linked by weak N—H⋯Cl hydrogen bonds into layers parallel to the bc plane. π–π inter­actions with centroid–centroid distances in the range 3.4452 (8)–3.8074 (8) Å are also observed

2-(5,6-Dihydro­benzimidazo[1,2-c]quinazolin-6-yl)phenol

The asymmetric unit of the title compound, C20H15N3O, contains two independent mol­ecules, each of which is disordered over two sets of sites corresponding to a rotation of approximately 180° of the dihydro­benzimidazoquinazoline moiety, with refined site occupancies of 0.7479 (13) and 0.2521 (12) for both mol­ecules. The pyrimidine rings are in sofa conformations. In one mol­ecule, the hy­droxy-substituted benzene ring forms dihedral angles of 83.9 (3) and 82.4 (4)° for the major and minor components, respectively, with the mean plane of the benzimidazole ring system. The corres­ponding dihedral angles in the other mol­ecule are 88.31 (14) and 85.8 (6)°. In the crystal, mol­ecules are linked via inter­molecular O—H⋯N and N—H.·O hydrogen bonds into chains along [100]

(E)-2-{[1-Carb­oxy-2-(1H-indol-3-yl)ethyl­iminio]meth­yl}-6-hy­droxy­phenolate

In the zwitterionic title compound, C18H16N2O4, the dihedral angle between the planes of the benzene and indole rings is 26.38 (10)°. An intra­molecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, mol­ecules are linked through N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds into infinite chains propagating in [010]

2-((E)-{2-[(1E)-(2,4-Dihydroxy­benzyl­idene)amino]phen­yl}iminiometh­yl)-5-hydroxy­phenolate methanol solvate

The asymmetric unit of the title compound, C20H16N2O4·CH3OH, contains two Schiff base zwitterions and two methanol solvent mol­ecules. The dihedral angles between the central benzene ring and the two outer benzene rings of the Schiff base are 2.57 (7) and 52.30 (7)° in one mol­ecule and 5.83 (7) and 49.82 (7)° in the other mol­ecule. Intra­molecular O—H⋯N and N—H⋯O hydrogen bonds generate S(6) ring motifs, whereas intra­molecular N—H⋯N hydrogen bonds generate S(5) ring motifs. In the crystal structure, O—H⋯O, hydrogen bonds and weak C—H⋯O inter­actions link the mol­ecules into one-dimensional chains along the b-axis direction and are further connected by O—H⋯O and weak C—H⋯O inter­actions into a three-dimensional network. C—H⋯π and π–π inter­actions [centroid–centroid distances = 3.6228 (9) and 3.6881 (9) Å] are also observed in the crystal structure