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An Fe[Cl.sub.3]-mediated intramolecular heterocyclization of 3-alkoxyimino-2-arylalkylnitriles is applied to prepare a series of functionalized N-alkoxyindole-3-carbonitrile derivatives. The novel synthetic method allows the N-moiety on the side chain to be annulated to the benzene ring as the final synthetic step which in turn facilitates the functionalization of the benzenoid portion of the indole at an early stage of the synthesis.

The synthesis, isolation, and characterization of hexakis(4-(N-butylpyridylium))benzene as both a hexacation and neutral molecule are reported.

The aggregates of multinuclear building units and deprotonation of tribenzimidazoyl influence the formation of silver (I) complexes.

The cytochrome P450 acts as an oxidant of halogenated benzene derivatives mediated by Compound I. These reactions in which there is selective elimination of halogen atoms can be utilized to tackle the environmental pollution caused by the aromatic halogen derivatives.

Various related compounds of hexaphenylbenzene are examined, which usually engage in hydrogen bonding and hence give rise to numerous hydrogen-bonded molecular crystals. The results show that the number of hydrogen bonds and the percentage of volume accessible to the guests are found to be highest in such complexes, which demonstrates the importance of maintaining a consistent molecular shape while determining the properties.

An efficient protocol is described for the synthesis of structurally diverse (diphenylphosphinoylmethyl)benzenes. The transformation and elaboration of 4-bromo-1,3-bis(diphenylphosphinoyl)benzene through the transition-metal-mediated procedures has produced functionalized (diphenylphosphinoylmethyl)benzenes.

Exposure of gold (Au) surfaces to ethynylbenzene in solution is studied. It is seen that ethynylbenzene forms monolayer structures on Au(111) surfaces by solution phase deposition and the deposited monolayers consists of a bound, oxygen-containing species.

Van der Waals (vdW) complexes of aromatic moieties are investigated to understand the intermolecular interaction between some small molecules (HF, [H.sub.2]O, N[H.sub.3], and C[H.sub.4]) and certain benzenoid ring system. The point dipole-quadrupole and point quadrupole-quadrupole interactions found in the complexes have accounted for the preferred orientations and the distributed multipole moments of the constituent atoms are found to give a quantitative description of the interaction in such complexes.

Molecular mechanics computational analysis is conducted to determine the energetic and structural modifications on the rotation of the central phenylene of 1,4-bis(3,3,3-triphenylpropynyl)benzene in the solid state. Results concluded that in absence of large quantities of free volume, rotational motion in the solid state might be coupled to correlated motions in the crystal lattice.

A new two-photon (TP) probe for the detection of free [Mg.sup.2+] ions in living cells and live tissues was developed. This probe can be excited by 880nm laser photons and is capable of imaging endogenous stores of free [Mg.sup.2+] in live tissues using TP microscopy.

The complex bioactive natural and unnatural benzopyran congeners were synthesized using one/two-step approaches. The congeners were synthesized by phenol directed intramolecular diastereoselective dipolar thermal/base catalyzed [2+] cycloaddition approach.

Azobenzene derivatives carrying a nitroxide radical (aminoxyl) were prepared and their photoisomerization reaction to the corresponding cis-isomers was investigated. The unsubstituted derivatives at the para position were found to undergo photoisomerizations by irrdiation and the intermolecular magnetic interactions were observed by structural change for each photochromic couple.

The influence of solvent, temperature and viscosity on the photoautomerization processes of a series of o-hydroxyarylbenzazoles is examined. All the compounds, including 2-(3'-hydroxy-2'-pyridyl)benzoxazole (HPyBO), have undergone an excited-state intramolecular proton transfer (ESIPT) from the hydroxyl group to the benzazole N3 to yield an excited tautomer in syn conformation.

The rearrangement of n(n = 1,...,19) Ar atoms around [Na.sup.+]-benzene clusters and an atom-bond potential energy surface are used to study the gradual evolution from cluster rearrangement to solvation dynamics. The results have shown that benzene molecule is strongly bound to [Na.sup.+] independently of the number of solvating rare-gas atoms, although due to the anisotropy of the interaction potential, the Ar atoms solvate the [Na.sup.+]-benzene cluster preferentially on the side of the cation.

Potential energy curves are produced for the halogen bonding interactions of several halobenzene-formaldehyde complexes. The results have shown that for most halogen substituents, a halobenzene and formaldehyde form stable halogen bonded complexes with interaction energies that increase as the size of the halogen substituent increases.

The B3LYP/6-31G* level of theory is used to study the geometry of multiply fused dehydrobenzo[12]annulenes [12]DBAs with various topologies, which are considered as graphyne fragments. The para-conjugation pathway of the bis(phenylethynyl)benzene unit has played a vital role in determining the electronic properties of multiply fused DBAs than the meta- and ortho-conjugation pathways.

A model similar to an isodesmic reaction is presented for describing, defining and calculating the interaction energies of the indirectly linked groups or atoms within one molecule, including nitro substitutes of methane, benzene and cubane. The results have proved that the so-called interaction energy is a new, quantitative and useful tool to evaluate the stabilities of nitro compounds.

Various studies and researches are conducted to observe the synthesis, resolution and X-ray structures of several exceptionally twisted polycyclic aromatic hydrocarbons, including different pentacenes and various dimethyl derivatives. The experimental geometry, as well as the observed racemization barrier for such compounds agree well with the theoretical studies and hence show that in spite of exhibiting high specific rotations, the molecules racemize slowly at room temperatures.

The preparation and structural characterization of silver(I) complexes of the arene-linked bis(pyrazolyl)methane ligands m-[[CH[(pz).sub.2]].sub.2][C.sub.6.][H.sub.4], ( and p-[[CH[(pz).sub.2]].sub.2][C.sub.6.][H.sub.4] and 1,3,5-[[CH[(pz).sub.2]].sub.3]C.sub.6.][H.sub.3] is described. The findings reveal that use of the tritopic ligand affords stoichiometry-dependent complexes containing either discrete dimeric metallacycles with equimolar amounts of silver salts and ligand or a polymer of metallacycles in the presence of an excess of silver salt.

The EPR spectroscopy is used to examine the orientation of paramagnetic liquid crystal (LC) (2S,5S)-2,5-dimetyl-2-heptyloxyphenyl-5-[4-(4-octyloxybenzenecarbonyloxy)phenyl]pyrrolidine-1-oxy molecules in a surface-stabilized liquid crystal (LC) cell. The order parameter is determined by measuring the temperature profile of the g-value and fitted it by use of the Haller equation.

The study about the first complete (d, T) phase diagram of benzene confined in silica-walled MCM-41 and SBA-15 showing the transition temperatures as a function of pore size is presented. Neutron diffraction measurements showed that for benzene the structures of the liquid or the crystal are not noticeably changed under confinement and proton NMR spin-spin and spin-lattice relaxation times show a slowdown of the overall dynamics of the confined phases compared to the bulk.

The preparation, crystal structures, characterization and relative stability of Forms I-IV of benzidine (B) are reported. The possibility of screening crystal samples by full structure determination afforded by the CCD detector diffractometer has facilitated the investigation.

The synthesis and coordination chemistry of a series of bis(benzene-o-dithiol) ligands are described that are able to form either dinuclear triple-stranded helicates or double-stranded helical complexes with titanium(IV) ions, depending on the ligand backbone. The analysis has shown that the type of bridging group between the benzene-o-dithiolato donor groups is responsible for the formation or absence of N-H...S hydrogen bonds.

The structure, dynamics and energetics of [[H.sub.2]Si[(Cp).sub.2]Zr[Me.sup.}][MeB([[C.sub.6][F.sub.5]).[sub.3].sup.-] and [[Me.sub.2]Si[(Cp).sub.2]Zr[Me.sup.}][MeB[([C.sub.6][F.sub.5]).[sub.4].sup.-]] ion pairs in benzene is reported. The simulations show that the tightly bound ion pair swings between minimum two geometries with a different coordination pattern of the F atoms to the Zr cation.

A method is suggested to construct good bias potentials ('balancing factors') to be used in expanded ensemble (EE) calculations of chemical potential of solution. The method uses a coupling parameter pathway that avoids large variations in free energy, and a bias potential construction that approximately eliminates the remaining free energy variations along the path.

The potential of tetrazolate-based ligands for forming metal-organic frameworks of utility in hydrogen storage is demonstrated with the use of 1,4-benzeneditetrazolate (BDT.sup.2-) to generate a series of robust, microporous materials. It is shown that the method for desolvating such compounds could dramatically influence the ensuing gas sorption properties.

Porous carbon materials with pore sizes from 3 to 200 nm were synthesized by reacting hexafluorobenzene with Na liquid at 623K. The self-generated NaF acted as the nanotemplate to shape the carbon material porous structure.

The title compound was synthesized to produce stacked benzene-like [Sn.sub.6.sup.6-] rings separated by alkaline-earth cations in analogy with reported stacks of aromatic cyclopentadienyl-like [Sn.sub.5.sup.6-] in [Na.sub.8-]Ba[Sn.sub.6]. The resulting compound has the correct stoichiometry with six tin atoms and six positive charges.

The interaction of the highly cross-reactive anti-PAH monoclonal antibody with four diastereomeric benzo[a]pyrene tetrols (BPTs) is studied by means of fluorescence line-narrowing spectroscopy. It is shown that the interaction of enantiomers of cis-BPT and trans-BTP with the antibody involves different complex geometries.

The neutron powder diffraction and inelastic neutron scattering (INS) spectra of the electron donor-acceptor complex, tetracyanoethylene-hexamethylbenzene is studied as a function of pressure. The PW91 vibrational frequency calculations have reproduced both the vibrational intensities and frequencies with relative accuracy.

Fresh DNA derivatives are synthesized having halogenated recognition bases or benzene rings and the effects of the modifications on the triplex stability as well as selectivity are evaluated. It is reported that the triplex-forming oligonucleotides (TFO) containing WNA-betaT and WNA-betaC stabilizes a TA or a CG interrupting site, respectively with high selectivity and stability.

A study investigates the electronic and magnetic properties of the proposed one-dimensional transition metal, benzene sandwich polymers by means of density functional calculations. Results indicate that the 1D organometallic sandwich polymers are possible candidates for spintronic devices for spin-polarized transport since the polymers with an inherently uniform size are supposed to be also ferromagnetic (FM).

Gas-phase electron diffraction and ab initio/density functional theory (DFT) MO calculations were used for determining the molecular structures of ethynylbenzene and s-triethynylbenzene. Ethynylbenzene possesses an inaccurate molecular structure in the ipso region of the benzene ring.

The electronic and photophysical properties of the new complexes were examined using UV-vis, fluorescence, and phosphorescence spectroscopies and electrochemical analysis. All four complexes display a weak metal-ligand charge-transfer absorption band that varies considerably with the phosphine ligand.

The synthesis, crystal structure, and magnetic characteristics of a new crystalline polymorphic phase of tetrakis(mu2-benzoato-O,O')-bis(dimethyl sulfoxide)dicopper(II), are investigated. The results show that 1a is a molecular solid featuring structural characteristics suitable for the coexistence of both magnetic phases in the bulk material.

The underlying mechanism of UV light-induced dissociation and visible light-induced reformation of vesicles formed by an azobenzene diblock copolymer was investigated. The study suggests a specific design principle for obtaining UV light-dissociable and visible light-recoverable vesicles based on azobenzene block copolymers.

A theoretical study of the low-lying electronic excitations in the [Pt(P((super n)Bu)3)2(ethynylbenzene)2] molecule is conducted. At the vertical geometry, the electron-hole pair breaks the symmetry of the molecule through a distortion along a b(sub 3u) mode, in agreement with the original conclusions of Emmert and group.

The absorption and emission spectra of the Pt(II) complexes containing N^C^N-coordinating tridentate ligands, platinum(II) 1,3-di(2-pyridyl)benzene chloride [Pt(dpb)Cl] and platinum(II) 3,5-di(2-pyridyl)toluene chloride [Pt(dpt)Cl], together with their corresponding free ligands, 1,3-di(2-pyridyl)benzene (dpbH) and 3,5-di(2-pyridyl)toluene (dptH) are analyzed. The results proved that the time dependent density functional theory approach is rational for analysis of the excited-state properties of the objective complexes.

The microsolvation structure of the [benzene--(methanol)(sub n)](super +) (n=1--6) clusters is analyzed by electronic and infrared spectroscopy. The most stable isomer of the n=1 cluster is suggested to be of the 'on-ring' structure where the nonbonding electrons of the methanol moiety directly interact with the pi orbital of the benzene cation moiety.

The synthesis and properties of a nucleic acid analogue consisting of a benzene-phosphate backbone are described. The building blocks of the nucleic acid analogue are composed of bis(hydroxymethyl)-benzene residues connected to nucleobases via the biaryl-like axis.

A study examines the synthesis of a series of new tetrameric sugar derivatives, one of which demonstrates highly pronounced hydrogelation properties. Detailed spectroscopic, thermal, and microscopic characterization of the resultant gel is provided together with the effect of pH and addition of salts to it.

The design of homogeneous catalysts based on Ir and other late transition metal complexes using O-donor ligands like acetylacetonate (aca), tropolone, aryloxides, catechols, hydroxyaetophenone to stabilize the complexes to the reaction conditions needed for generating functionalized products is discussed. The outcome of the studies helps to utilize, design new, more effective, thermally protic-and oxidant-stable O-donor catalysts for hydrocarbon conversion.

The ligand based reduction chemistry of (EPh)(super -) ligands in a metallocene environment is compared to the sterically induced reduction chemistry of the (C5Me5)(super -) ligands in (C5Me5)3Sm by synthesizing complexes like, (C5Me5)2Sm(EPh) (E=S, Se, Te) and treating them with substrates reduced by (C5Me5)3Sm, cyclooctatetraene, azobenzene, phenazine. These benzene chalcogenolate complexes were identified by X-ray crystallogarphy.

Abstract -- The mechanism of the electrochemical oxidation of iodide in the presence of 4-toluenesulfinic acid was studied in an aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results [...]

Low-temperature isomeric energies, structures, and properties of benzene-cyclohexane clusters are investigated via Monte Carlo simulations. The results identify a single parallel-displaced dimmer isomer, MP2 optimizations and frequency calculations support the Monte Carlo dimmer structure and identify the van der Waals mode observed in vibronic spectra.

The hydride, fluoride, and pentafluorophenylmetallocenes are isolated and characterized by X-ray crystallography. A monomeric metallocene hydride of cerium undergoes H/F exchange with fluoroaromatics is showed and DFT calculations provide details about the relative activation barriers for the reaction pathways.

The stabilities of hitherto unknown structures with the C(sub 6)H(sub 6) structural formula is identified and studied. Ab initio (MP2, CCSD9T)) and hybrid density functional theory (B3LYP) calculations with up to triple-zeta basis set were done to locate all possible minima, where each carbon in the molecule is tetracoordinate, on the C(sub 6)H(sub 6) potential energy surface.

Density functional theory is utilized to determine whether the addition of O2((super 3)sigma(sub g)) to 2-oxepinoxy radical, a proposed intermediate in the unimolecular decomposition of phenylperoxy radical, followed by unimolecular rearrangement and decomposition results in the formation of experimentally detected C1-C5 products through oxidative combustion of benzene.

A study on the ability of the 2-pyridyl and 1-isoquinolyl groups to direct metalation in the benzene series is reported. Comparisons revealed that the fluoro units was the stronger directing group for deprotonation than the 2-pyridyl.

Density functional calculations are carried out on series of linearly annelated ancenes and their BN analogues. Nucleus independent chemical shift (NICS) values in acenes suggest that the aromaticity of the inner rings is more than that of benzene, whereas in BN-acenes there is no substantial change in the aromaticity of the individual rings.