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A kinetic study on [S.sub.N]Ar reactions of 1-aryloxy-2,4-dinitrobenzenes (1a-1h) with a series of cyclic secondary amines in 80 mol% water - 20 mol% DMSO at 25.0 [+ or -] 0.1 [degrees]C is reported. The plots of [k.sub.obsd] versus amine concentration curve upward except for the reactions of substrates possessing a strong electron-withdrawing group in the leaving aryloxide with strongly basic piperidine. The curved plots indicate that the reactions proceed through both uncatalytic and catalytic routes. Linear Bronsted-type plots have been obtained for the uncatalyzed and catalyzed reactions of 1-(4-nitrophenoxy)-2,4-dinitrobenzene (1a) with [[beta].sub.nuc] = 0.84 and 0.78, respectively. The Yukawa-Tsuno plot for the uncatalyzed reactions of 1a-1h with piperidine results in an excellent linear correlation with [rho] = 1.66 and r = 0.31. In contrast, rate constants for catalyzed reactions are independent of the electronic nature of the substituent in the leaving group. The current [S.sub.N]Ar reactions have been proposed to proceed via a zwitterionic intermediate (MC[+ or -]) that partitions to products through uncatalytic and catalytic routes. The catalyzed reaction from MC[+ or -] has been concluded to proceed through a concerted mechanism with a six-membered cyclic transition state ([TS.sub.cycl]) rather than via a stepwise pathway with a discrete anionic intermediate ([MC.sup.-]), the traditionally accepted mechanism. Medium effects on the reactivity and reaction mechanism are discussed. Particularly, hydrogen bonding of the amines to water precludes formation of kinetically significant dimers found in some aprotic solvents; no explicit role for water in the catalytic transition state is required or proposed. The specific stabilization of the leaving aryloxides substituted with strong electron-withdrawing groups accounts for the lack of the catalytic pathway in these systems (1a-1c) with piperidine nucleophile. Key words: [S.sub.N]Ar reaction, Bronsted-type plot, Yukawa-Tsuno plot, zwitterionic intermediate, six-membered cyclic transition state. Resume : Nous presentons une etude cinetique des reactions [S.sub.N]Ar de 1-aryloxy-2,4-dinitrobenzenes (1a-1h) avec une serie d'amines secondaires cycliques dans un melange a 80 mol% eau - 20 mol% DMSO a 25,0 [+ or -] 0,1 [degrees]C. Les courbes de [k.sub.obsd] representees en fonction de la concentration d'amine s'incurvent vers le haut, sauf celles des reactions de substrats dont le groupe partant aryloxyde presente un substituant fortement electroattracteur avec la piperidine, une amine fortement basique. Les traces courbes indiquent que les reactions s'effectuent a la fois par des voies catalytiques et non catalytiques. Nous avons obtenu des courbes de type Bronsted lineaires pour les reactions non catalysee et catalysee du 1-(4-nitrophenoxy)-2,4-dinitrobenzene (1a), dont les coefficients [[beta].sub.nuc] sont de 0,84 et 0,78 respectivement. La courbe de Yukawa-Tsuno pour la reaction non catalysee des composes 1a-1h avec la piperidine presente une excellente correlation lineaire, dont les parametres [rho] = 1,66 et r = 0,31. En revanche, les constantes de vitesse des reactions catalysees sont independantes de la nature electronique du substituant present sur le groupe partant. Nous avons pose l'hypothese que les reactions [S.sub.N]Ar en question procedent par un intermediaire zwitte-rionique (MC[+ or -]) qui se partage en produits par des voies catalytiques et non catalytiques. Nous avons conclu que la reaction catalytique de l'intermediaire MC[+ or -] s'effectue via un mecanisme concerte en passant par un etat de transition cyclique a six membres ([ET.sub.cycl]) plutot que via un mecanisme sequentiel, passant par un intermediaire anionique discret (MC), qui est le mecanisme traditionnellement admis. Nous abordons les effets du milieu sur la reactivite et le mecanisme de reaction. Notamment, les liaisons hydrogene entre les amines et les molecules d'eau empechent la formation de dimeres, favorable sur le plan cinetique, qui est observee dans certains solvants aprotiques; aucun role explicite de l'eau dans l'etat de transition de la voie catalytique n'est necessaire ni n'est propose. L'absence de la voie catalytique dans la reaction des systemes (1a-1c) avec la piperidine comme nucleophile s'explique par la stabilisation specifique des groupes partants aryloxydes portant des substituants fortement electroattracteurs. [Traduit par la Redaction] Mots-cles : reaction [S.sub.N]Ar, courbe de type Bronsted, courbe de Yukawa-Tsuno, intermediaire zwitterionique, etat de transition cyclique a six membres., Introduction In the toolkit of the synthetic organic chemist involved in the design and preparation ofnew aromatic compounds, nucleophilic aromatic substitution on electron-deficient substrates is a versatile, even essential, implement. [...]

In this study, the adsorption behaviors of methanol, methanal, toluene, ethylbenzene, and styrene molecules in FAU, FER, CON, and MWW zeolites were investigated. The adsorption isotherms of the five adsorbates in the four zeolites at 298 and 350 K were simulated using grand canonical Monte Carlo simulations. Moreover, binary component adsorptions were considered. The results revealed that the saturated adsorption capacity ofsingle components in different zeolites decreased in the order of FAU > MWW > CON > FER, and the adsorption capacity of the five adsorbates in the same zeolite decreased in the order of methanal > methanol > toluene > styrene > ethylbenzene. The equilibrium adsorption capacity slightly decreased with increasing temperature. In terms of binary component adsorption, intense competition existed between the smaller adsorbed molecules. As the differences among the molecular structures increased, the competition in adsorption became more intense. Key words: zeolite, adsorption, grand canonical Monte Carlo simulation, adsorption isotherm, molecular simulation. Dans le cadre des present travaux, nous avons etudie le comportement d'adsorption des molecules de methanol, de methanal, de toluene, d'ethylbenzene et de styrene sur des zeolites de structure FAU, FER, CON et MWW. Nous avons simule les isothermes d'adsorption des cinq adsorbats sur les quatre zeolites a 298 K et a 350 K en utilisant la methode Monte-Carlo dans l'ensemble grand canonique. En outre, nous avons etudie le cas des adsorptions de composantes binaires. En ce qui concerne les composantes uniques, les resultats ont revele que la capacite de saturation de leur adsorption sur differentes zeolites diminuait selon l'ordre FAU > MWW > CON > FER et que la capacite d'adsorption des cinq adsorbats sur une meme zeolite diminuait selon l'ordre methanal > methanol > toluene > styrene > ethylbenzene. La capacite d'adsorption a l'equilibre diminuait legerement en fonction de l'augmentation de la temperature. En ce qui concerne l'adsorption de composantes binaires, la competition pour l'adsorption etait plus forte entre les molecules de plus petite taille. A mesure que la difference entre les structures moleculaires augmentait, la competition pour l'adsorption s'intensifiait. [Traduit par la Redaction] Mots-cles: zeolite, adsorption, simulation de Monte-Carlo dans l'ensemble grand canonique, isotherme d'adsorption, simulation moleculaire., Introduction Styrene is an important monomer that is industrially applied for the synthesis of plastics and rubbers. (1) It is traditionally synthesized from benzene and ethylene, which is a complicated [...]

Abstract: (benzene)Cr[(CO).sub.3] was claimed to be more aromatic than benzene, based on the central [.sup.1]H Me chemical shifts in dimeth-yldihydropyrene annulated to it. In this paper, several dihydropyrenes are computationally [...]

Abstract: The crystal structure of 4-Methyl-N-(1-phenylethyl)-N'-(1-phenylethylidene) benzene sulfonohydrazide is disclosed, which is obtained from direct reaction between acetophenone tosylhydrazone and potassium tert-butoxide. Reaction mechanisms and the corresponding energy barriers were [...]

Monoalkyl esters of benzene-1,2-dicarboxylic (phthalic) acid have not been reliably characterized by analytical parameters for their chromatographic and chromatospectral identification. Mass spectra of a series of monoalkyl phthalates (R = [C.sub.1]-[C.sub.8]) are discussed; their gas chromatographic retention indices on the RTX-5 polydimethylsiloxane stationary phase (5% phenyl groups) are determined. A linear dependence of indices on the number of carbon atoms in n-alkyl fragments of molecules and a correlation between the indices of any monoalkyl phthalates and corresponding diesters were used for the control of the data obtained. Using the last correlation, we found that most part of index values of mono (2-ethylhexyl) phthalate given in literature is wrong and, therefore, the results of identification of this compound in various samples must be revised. It was found that simplest monoalkyl phthalates are unstable during gas chromatographic separation, which may result in distortions of their mass spectra. To compare with monoalkyl phthalates, a similar series of monoesters of (Z)-butenedioic (maleic) acid was characterized. Retention indices of monoalkyl phthalates in reversed phase HPLC were determined and discussed. Keywords: phthalic acid, maleic acid, monoalkyl esters, gas chromatographic retention indices, reversed phase HPLC, mass spectrometry, Present-day chromatographic and chromatospectral identification of organic compounds in complex mixtures implies a comparison of their mass spectra and chromatographic retention parameters (indices) with reference data. Algorithms of such comparison [...]

Now that we have completed our discussion of benzene rings and the infamous 'benzene fingers,' the next topic on our hydrocarbon hit parade is carbon-carbon double bonds. C=C bonds, otherwise [...]

Following up on the last installment, we examine the infrared (IR) spectra of mono- and disubstituted benzene rings. We examine numerous example spectra and learn how the position of C-H [...]

The present study describes a preparative gas chromatographic (GC) approach employed to study a series of products arising from reaction of phenylacetylene with para-substituted aryl-iodides under Sonogashira catalysis conditions. GC analysis resolves the isomers from each reaction; however, it cannot provide structural details (their MS data are virtually identical). Since classical liquid chromatography cannot resolve the isomers, preparative-scale GC is the only practical approach to provide further spectroscopic characterization of the isomers. The products are well separated by GC so a single thick-film capillary column is adequate for this case, with operation up to ~+300[degrees]C. By collection of 50+ repeat injections, sufficient material could be isolated for [sup.1]H NMR spectral analysis of the isomers, and for one isomer (isomer I) of a number of analogous related catalytic reaction mixtures, X-ray crystal structure determination enabled complete structural elucidation (absolute configuration) of the substitution pattern of the structure of this isomer. This confirmed isomer I to be the 2-para-aryl-substituted 1,3,5-triphenylbenzene product in all cases. [sup.1]H NMR spectra of isomer I products generally had similar patterns but differed markedly from the second major isomer product (isomer II). 10.1021/ac100417h

[TiCl.sub.4]-mediated Friedel-Crafts benzylation of benzene with 8-(bromomethyl)[2.2]metacyclophanes to afford 8-benzyl[2.2] metacyclophanes is described. Substituent effect through space on the rate of the benzylation of benzene with a bromomethyl group attached on the opposite aromatic ring was first found in this investigation. Interestingly, the introduction of the substituents at the internal position 16 tends to promote the present benzylation reaction rate 1.8-3.8 times. It was found that the benzyl cation intermediate was stabilized by the the direct through-space cation-πt interaction among the opposite benzene ring in the benzylation of [2.2]metacyclophane systems. Key words: cyclophanes, Friedel-Crafts benzylation, benzyl cation intermediate, through-space electronic interaction. On decrit la reaction de benzylation du benzene par le 8-bromomethyl)[2,2]metacyclophanes par la meethode de Friedel-Crafts catalysee par le [TiCl.sub.4]. Dans ce travail, on a mis en evidence pour la premiere fois, un effet de substituant qui se fait sentir a travers l'espace sur la vitesse de benzylation du benzene en raison d'un groupe bromomethyle attacheee sur le noyau aromatique oppose. Il est interessant de noter que l'introduction de substituants a la position interne 16 tendent a acceterer les vitesses de reaction de benzylation par des facteurs allant de 1,8 a 3,8. On a trouvee que le cation benzylique intermeediaire est stabilise; par une interaction cation-π directe a travers l'espace du noyau benzeenique oppose dans la benzylation de systemes [2,2] meetacyclophanes. Mots-cles: cyclophanes, benzylation suivant Friedel-Crafts, cation benzylique intermeediaire, interaction electronique a travers l'espace., Introduction The geometry of the [2.2]metacyclophane ([2.2]MCP) skeleton is known in detail from an X-ray structural analysis. (2,3) The crystal consists of discrete molecules, each of which has a center [...]

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 synthesis and characterization of 1,4-difluorobenzo[c]phenanthrene (1,4-DFBcPh) was carried to understand its extent of DNA binding by the metabolities of dihydrodiol and diol epoxides. The findings showed that increased molecular distortion decreased metabolic activation to the terminal metabolities and the formation of diol epoxide metabolites was the DNA-damaging species.

The exchange of the guest [Mn.sup.2} ions in [Mn.sub.3][[[([Mn.sub.4]Cl).sub.3][(BTT).sub.8][(C[H.sub.3]OH).sub.10]].sub.2] (BTT = 1,3,5-benzenetristetrazolate) with selected cations has resulted in the formation of isostructural framework compounds. The [Co.sup.2}-exchanged compound has displayed an initial enthalpy of adsorption of 10.5 kJ/mol, which is the highest yet observed for a microporous metal-organic framework.

The synthesis and characterization of a new class of highly fluorescent and stable carbazole-based dendrimers that contain the ethynylbenzene and diethynylbenzene cores are presented. The results have indicated the dendrimers potential use as blue-emitting materials in organic light-emitting diodes (OLEDs).

Several new ferrocene derivatives bearing two donor-acceptor systems are reported in which the ferrocene unit has acted both as a donor group and as a rotating spacer. These ferrocene sensors have allowed the naked-eye selective colorimetric detection of copper[II] cation and of benzoate, acetate, or cyanide anions, all anions of special toxicological and biological relevance.

A novel bimetallic complex was prepared in the bridging-ligand 1-methyl-3,5-bis(2,2':6',2'-terpyridin-4'-yl)benzene which was designed to induce ferromagnetic coupling of the two [Yb.sup.III] centers is 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.

The preparation and full characterization of the mononuclear neutral complexes [P[t.sup.II]([super t]bpy)(A)] and [P[t.sup.II]([super t]bpy)(B)] (where bpy = 4,4'-di-tert-butylbipyridine, (A) = 3,6-bis(trimethylsilyl)benzene-1,2-(dithiolate(2-) and (B) = 1,2-bis(4-tert-butylphenyl)ethylene-1,2-dithiolate(2-)) is described. The cations are shown to dimerize in C[H.sub.2]C[l.sub.2] solution affording diamagnetic dimers.

1,3,5-Triethylbenzene and pyrogallol are used for the synthesis of new tripodal receptor bearing three catechol subunits on a benzene platform and the binding ability of the tricatecholic receptor for carbohydrate detection is examined. The results have shown that the tripodal catecholic receptor binds the octyl glycosides with different affinities and with a 6-fold selectivity factor of the [alpha]-mannoside over the [beta]-glucoside.

The photochemistry of isomeric methoxyphenyl chlorides and phosphates were analyzed in different solvents and in the presence of benzene and were found to involve the triplet state. Results revealed that a unitary mechanism is proposed for the photochemistry of the three chloroanisoles and of the corresponding phosphates in polar solvents and involves a heterolytic [S.sub.N]1 path.

A study is conducted to demonstrate that equatorial 4-O-benzyl ethers are removed with moderate selectivity on exposure to dichlorodicyanoquinone in wet dichloromethane at room temperature in the presence of other benzyl ethers in glycopyranosides and glycothiopyranosides. It is inferred that selective cleavage of the 4-O-benzyl ethers derives from antiperiplanar nature of C4-O4 and C5-O1 bonds maximizes the electron-withdrawing properties of the latter and hastens the decomposition of the radical cation.

The feasibility of ruthenium-catalyzed cyclization of 2-alkyl-1-ethynylbenzenes through benzene 1,5-hydrogen shift activated by a cationic ruthenium-vinylidine intermediate is studied. It is found that catalytic cyclization of 2-alkyl-1-ethynylbenzene derivatives has formed 1-substituted-1H-indene products.

Experimental and computational were used to study the reaction of benzene-tropothione and identify three equimolar isomeric products. The findings suggest that the biradical character of the benzyne has a key role in the present reaction.

Emission from charge recombination between radical cations and anions of various tetrakis(phenylethynyl)-benzenes (TPEBs) were measured during pulse radiolysis in benzene (Bz). The three types of charge-transfer pathways suggest that the emission spectra of TPEBs with intramolecular charge transfer (ICT) character depend on the substitution pattern and the various kinds of donor and acceptor groups during pulse radiolysis in Bz.

A study was conducted to examine the reactions of 1,3-disubstituted isobenzofurans with the fullerene [C.sub.60] in the context of an approach to open a large orifice on the fullerene framework. The thermal stability of the adducts toward retro-Diels-Alder fragmentation differs greatly in solution from that in the solid state which suggest that they could be stored at room temperature in the solid state for several weeks without significant decomposition but have to be handled within several hours in solution.

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.

The syntheses and characterization of four metal-organic frameworks (MOFs) containing chiral channels by using 4,4',4'-s-triazine-2,4,6-triyltribenzoate (TATB) ligand pairs and an hourglass secondary building unit (SBU) are described. It is seen that thermal stability and framework stability after guest removal improve by SBU stabilization without a significant joint sacrifice of porosity.

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.

The regeneration of a series of 2,3-dihydrobenzo[b]selenophene-5-ol derivatives by water-soluble N-acetylcysteine in a two-phase model system for lipid peroxidation is investigated. The results have shown that the regeneration and catalytic performance is dictated by the number and position of methyl substituents present in the phenolic ring of the antioxidant.

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.

The electrosynthesis, isolation and characterization of reaction products between [C.sub.60.sup.2-] and benzyl bromide in PhCN are reinvestigated. The visible and near-infrared spectra of the monoanion and dianion of 1,2-[(PhC[H.sub.2]).sub.2][C.sub.60] are described.

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.

The bonding arrangement of benzene-1,3-diamidoethanethiol (BDET[H.sub.2]) to the metals Cd, Hg, and Pb, along with the full characterization data of the BDET-M compounds is reported. The results have supported the presence of a linear coordination environment for BDET-Hg and it is likely that the BDET-Cd and BDET-Pb structures are four-coordinate and distorted tetrahedral.

A cationic rhodium(I)/Segphos complex has catalyzed an enantio- and diastereoselective intermolecular [2+2+2] cycloaddition of 1,2-bis(arylpropiolyl)benzenes with various monoalkynes in order to produce axially chiral 1,4-teraryls possessing an anthraquinone structure. A thermal intramolecular [4+2] cycloaddition of 1,2-bis(arylpropiolyl)benzenes has proceeded at 60 [degree]C to produce aryl-substituted naphthacenediones in moderate to good yields.

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 coordination assemblies resulting from the complexation of 1,3,5-tri(4-sulfophenyl)benzene, [L.sup.3-], with copper(II) in the presence of pyridine are analyzed. The results have given insights into the subtleties of designing coordination polymers and open-channel solids and three different single crystalline solids are obtained from an initial crystallization.

The synthesis, photochromism, and optical properties of a chiral heliconoid diarylethene that shows a large change in specific optical rotation induced by photochromism is reported. The diarylethene possessing one [4]thiaheterohelicene and one benzothiophene with a chiral methoxymethoxyethyl group on its C-3 position was proved to work as a switch of specific optical rotation at a wavelength at which both colored and colorless forms have no absorption in solution.

Emission of benzene molecules by 5-keV cluster bombardment of a range of carbon projectiles from [C.sub.6][H.sub.6] to [C.sub.180] is studied by a coarse-grained molecular dynamics (MD) technique. This approach permits calculations that are not feasible using more complicated potential energy functions, particularly as the interesting physics associated with the ion impact event approaches the mesoscale. These calculations show that the highest ejection yields are associated with clusters that deposit their incident energy 15-20 [Angstrom] below the surface. The highest yield for the projectiles is produced by the [C.sub.20] and [C.sub.60] projectiles. The results from the MD simulations are also compared favorably to an analytical model based on fluid dynamics to describe the energy deposition. The analytical model is then utilized to extend the range of the calculations to higher incident energies. The issue of the relative amount of chemical fragmentation and intact molecular desorption is also examined for the benzene crystal. These results show that damage accumulation at high-incident fluence should not be problematic and that it should be possible to perform molecular depth profiling via secondary ion mass spectrometry experiments. In general, the approach presented here illustrates the power of combining a simplified MD method with analytical strategies for describing a length scale that is difficult to achieve with traditional MD calculations.

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 synthesis of [[{Ru(typ)(thd)}.sub.2]([mu]-dicyd)][P[F.sub.6]] with tpy = 2,2':6',2'-terpyridine and thd = 2,2,6,6-tetramethyl-3,5-heptanedione, including the crystal structure in its +2 form is reported. Multiple spectroscopic, electrochemical, and spectroelectrochemical investigations have revealed the influence of the dicyanamidobenzene bridging ligand system on the intramolecular electron transfer abilities of binuclear ruthenium complexes.

The time-resolved fluorescence measurement during the pulse radiolysis of 9-cyano-10-phenylanthracene (PEA) and 9-cyano-10-phenylethynylanthracenes in benzene is used to study their emissions having donor as well as acceptor substituents. Results reveal that though the introduction of the ethynyl linkage for RA provides broad emission, which covers the visible region, it also causes aggregation to form excimer, leading to a reduction in the emission efficiency due to the aggregation formed.

The synthesis of new type [a] and [b] benzoxanthene dye frameworks is described. It is shown that a type [a]benzofluorone, seminaphtho[a]fluorone (SNAFR-1), displays unique properties, including white light emission as well as excitation over a 400 nm range and the compound can also be used in cellular imaging studies.

Sum frequency generation (SFG) vibrational spectroscopy, high-pressure scanning tunneling microscopy (HP-STM) and reaction turnover studies were used for the first time to explore and identify the surface species present during benzene hydrogenation in the presence of excess of hydrogen and in a range of temperatures (300-440 Kelvin). Small ordered regions which corresponded to the c(2X [square root of 3] X 3)rect structure, in which each molecule is chemisorbed at a bridge site, were imaged in a 10 Torr background of benzene and individual physisorbed benzene molecules were observed between these ordered regions.

The dynamic-kinetic resolution of different benzoins using a lipase-ruthenium-catalyzed transesterification in organic solvents to obtain conversions up to 90% maintaining the excellent enantioselectivity in all cases is described. In all cases, the particular stereobias of the lipase toward the racemic substrates allows the production of the opposite enantiomer of that one described through a different enzymatic methodology.

An experiment was conducted to develop an alkyne-azide cycloaddition based route to various C-glycoclusters featuring 1,2,3-triazole rings as linkers and different scaffolds. Each cycloaddition occurred with high regio-selectivity to give exclusively the 1,4-disubstituted triazole ring in very high yield up to an average value of 98%.

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.