Complexes of Zinc-Coordinated Heteroaromatic N-Oxides with Pyrene: Lewis Acid Effects on the Multicenter Donor-Acceptor Bonding.

4-Nitroquinoline-N-oxide (NQO) and 4-nitropyridine-N-oxide (NPO) are important precursors for the synthesis of substituted heterocycles while NQO is a popular model mutagen and carcinogen broadly used in cancer research; intermolecular interactions are critical for their reactions or functioning in vivo. Herein, the effects of the coordination of N-oxide's oxygen atom to Lewis acids on multicenter donor-acceptor bonding were explored via a combination of experimental and computational studies of the complexes of NQO and NPO with a typical π-electron donor, pyrene. Coordination with ZnCl increased the positive electrostatic potentials on the surfaces of these π-acceptors and lowered the energy of their LUMO.

Luminescent properties of chameleon-like metal-organic framework between zinc(II) dichloride and two quinoline-N-oxide molecules.

Zinc compounds in the form of inorganic/organic hybrids containing both zinc halides and heterocyclic ligands show various interesting optical and physicochemical properties. Due to these properties, there is a potential for development of various innovative technologies and applications within the life sciences. In this study, experimental and theoretical results on the absorption and emission (steady state and time-resolved) properties of the hybrid ZnCl(QO) complex formed between ZnCl and quinoline N-oxide, have been reported.

Complexes of Diiodine with Heteroaromatic -Oxides: Effects of Halogen-Bond Acceptors in Halogen Bonding.

Halogen bonding (XB) in complexes of diiodine with heteroaromatic -oxides was examined via a combination of UV-vis spectral and X-ray structural measurements, as well as computational analysis. While all of these associates were formed by analogous I···O bonds, they showed considerable variations of formation constants (5-1500 M) and intermolecular I···O bond length (2.3-3.

Photophysical behavior of a potential drug candidate, trans-[2-(4-methoxystyryl)]quinoline-1-oxide tuned by environment effects.

Styryl and/or quinoline structural fragments, present in a large number of bioactive substances, inspired the design of various new drug candidates. In this paper, we describe the photophysical behavior of trans-[2-(4-methoxystyryl)]quinoline-1-oxide (trans-MSQNO) on the basis of X-ray analysis data, theoretical calculations as well as steady state and time-resolved spectroscopy experiments in various media. The molecule crystallizes in orthorhombic unit cell containing eight molecules of N-oxide, space group Pbca.

Ultrafast excited state dynamics of trans-[4-(4'-dimethylaminostyryl)] pyridine N-oxide in solution: femtosecond fluorescence up-conversion and theoretical calculations.

The results of the steady-state and time-resolved fluorescence-spectroscopy measurements and DFT calculations for trans-[4-(4'-dimethylaminostyryl)] pyridine N-oxide (trans-DPO) in various solvents are presented. These results are similar to those reported in the literature for trans-4-(dimethylamino)-4'-cyanostilbene (DCS) where the S1 emissive state shows the charge-transfer (CT) nature. Alcohol solvents, however, have aroused our particular interest because hydrogen-bonded complexes are formed between them and the trans-DPO molecule.

X-ray crystal structure and magnetic and photophysical properties of novel copper(II) N-oxide adduct [(4-MPyO)2(CuCl2)2(H2O)(C2H5OH)] (4-MPyO = 4-(4-methoxystyryl)pyridine N-oxide).

A new mixed adduct, (4-MPyO)2(CuCl2)2(H2O)(C2H5OH) [where 4-MPyO is the 4-(4-methoxystyryl)pyridine N-oxide], was obtained for the first time. It has been characterized by X-ray studies, IR, electronic absorption, and emission spectra, lifetime measurements, and variable-temperature magnetic susceptibility measurements in the range 80-300 K. The single-crystal X-ray diffraction shows that the geometry around both of the copper(II) ions can be described as a tetragonal pyramid with a trapezoidal base at the corners of which are two oxygen atoms of N-oxide and two chlorine atoms.

Dichlorobis(2-methylquinoline N-oxide-kappaO)zinc(II) from powder data.

The crystal structure of the title compound, [ZnCl(2)(C(10)H(9)NO)(2)], has been determined from laboratory powder diffraction data. Although the powder pattern was initially indexed with tetragonal unit-cell dimensions, the correct solution was found in an orthorhombic space group using a combination of grid-search and simulated-annealing techniques. The subsequent bond-restrained Rietveld refinement gave bond lengths and angles within expected ranges.