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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.

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.

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.

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.

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.

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).

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 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.

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.

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.

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.

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.

Optical and conductivity detection were used to study the reaction between deoxyribose radicals (dR) and benzotriazine compounds. The results give a mechanistic model showing the way tirapazamine interacts with the ribose component of DNA after the one-electron reductions.

UV photolysis of 1,4-diaminobenzene isolated in a low-temperature argon matrix is studied by Fourier transform infrared spectroscopy with the aid of the density-functional theory calculations. Optimized structures of 1,4-diaminobenzene ,4-aminoanilino radical, and 2,5-cyclohexadiene-1,4-diimine are compared with one another.

Model 1,4-bis(styryl)benzene derivatives related to poly(2-bromo-5-methoxy-1,4-phenylenevinylene) are synthesized to probe the effect of bromination on excited-state behavior of conjugated phenylenevinylene analogues. Solution absorption maxima at about 385 nm, without evidence of excimer formation up to 100 mu M are seen.

Hexakis (4-carbamoylphenyl)benzene (1) as a new host molecule directed toward microporous organic solids are synthesized, and characteristics of the network morphology are examined. The present results suggest that the network morphology of a 3-D hydrogen bonded porous network in an organic host lattice without self-interpenetration would be affected by the properties of the crystallization solvents.

The gas-phase heat of formation (DeltaH (subf, 298)) of the 1,3,5-tridehydrobenzene triradical has been determined by using a negative ion thermochemical cycle. The trends in the first, second, and third bond dissociation energies of the benzene are similar to those found for cycloprophane, suggesting a cycloprophenyl-like electronic structure within the six-membered ring of the 1,3,5-benzene triradical.

An investigation is carried on various competing mechanisms involved in the early stages of the decomposition of a 'push-pull' aromatic (1,3,5-triamino-2,4,6-trinitrobenzene, TATB), and particularly on how hydrogen transfer affects the competition between ring closure and single bond scission. It is observed that the hydrogen motion forms a biradical state, which is suggested as the precursor to further decomposition products, such as benzofurazans.

Azobenzene and 4-aminoazobenzene reacts with the PdCl(sub2)(CH(sub3)CN)(sub2) complexes to produce a new class of doubly cyclopallated complexes. A description of simple synthesis of these complexes and structural characterization of X-ray analysis and NMR spectroscopy is presented.

The article explains the various mechanisms that are involved in the fast-photon-mode reversible handedness inversion of different self-organized helical superstructures. The two light-driven cyclic azobenzenophanes observed in the study are shown to exhibit extremely high solubility and helical twisting power.

Several studies are conducted to explain the redox behaviour exhibited by the synthetic models of the [FeFe]-hydrogenase with the amine cofactor and its N-benzyl derivative. The present azadithiolate cofactor is shown to play an extremely significant role in these models.