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The analysis of the structural, infrared spectra and electronic properties of the N7, N9-dimethylguaninium chloride is presented and the study of the interaction of one cation with one to four chlorine anions and one chlorine anion with two cations is described.

Several straightforward nucleophilic displacement reactions are used for an efficient synthesis of a large number of functionalized heteroatom-bridged calix[2]arene[2]triazines compounds on the larger rim in good yields. The resulting compounds are found to contain several amino groups, which makes them form numerous complexes with [Cu.sup.2+] ions, hence producing a chelating interaction effect.

Titanocene monochloride has catalyzed the homocoupling of benzylic halides and benzylic gem-dibromides in order to give the corresponding bibenzyl and stilbenyl systems. The exposure of benzylic bromides to Ti(III) in the presence of aldehydes has given rise to the Barbier-type products.

Several 1,3,5-tricarbonyl derivatives were prepared by reaction of 1,3-bisS9ilyl enol ethers) with acid chlorides under mild conditions. 1,3-bis(silyl enol ethers) were derived form methyl acetoacetate and the use of 1,3-diketone-derived 1,3-bis(silyl enol ethers) resulted in functionalzation of the central carbon atom of the bis (silyl enol ethers).

The effects of an ester group as an alkyne substituent on the reactivity of propargylic enynes, which inhibits the Rautenstrauch process, are analyzed. The steric interactions in the transition structure have provided different hyperconjugation interaction energies that have helped in determining the magnitude of the energy barrier for the rate-limiting H-abstraction step.

In-situ scanning tunneling microscopy in combination with in-situ surface X-ray diffraction, with a particular focus on adsorbate and potential dependent surface relaxation phenomena, is used to study the surface structure of Cu(100) modified by chloride and iodide in an electrochemical environment. The findings suggest a predominantly ionic nature of Cl-Cu bond under the given electrochemical conditions and the electrochemical annealing effect is mediated by weakened Cu-Cu bond.

An attempt is made to study the kinetics of the reaction of Br atoms with C[H.sub.2]ClBr with the main objective to provide data for comparison with theory in a wide range of temperatures. The absolute reaction kinetics method of laser flash photolysis coupled with Br atom resonance fluorescence detection and three different relative-rate methods with gas-chromatographic analysis were applied to carry out experiments.

A theoretical study of the low-lying singlet and triplet states of CIONO is presented along with calculations of excitation energies and oscillator strengths using multireference configuration interaction. A comparison between the calculated electronic energies related to the two dominant excited states of CIONO and BrONO indicates that the transitions lie about 0.6 eV higher if bromine is replaced by chlorine.

A high-level ab initio calculation of several complexes of chloride and bromide anions with trifluro-s-triazine (TFZ) and s-triazine (TAZ) is reported to study the additivity of the anion-pi interaction. The results based on anion pi, anion pi2, and anion pi3 reveal additivities of both the geometries and the binding energies.

The density functional theory (DFT) studies on mono- and dichloro derivatives of benzene, naphthalene, B12H(sub 12)(super 2-), four-atom-sharing condensed systems B20H16, and monocarborane isomers are used to compare the variation of relative stability and aromatically between condensed aromatics. The trends in the variation of the relative energies and aromaticity in these two- and three-dimensional systems are similar and the compatibility of the cap and ring orbitals decides the relative stability of CB19H16.

The synthesis and structural characterization of two manganese complexes, (py2(NMe)(sub 2))Mn(super II)Cl2 (1) and [(py2(NMe)(sub 2))Mn(super III)F2](super +) (2), as well as the study of the electronic properties of Mn(III) complex by density functional theory (DFT) calculations and high-field and high-frequency electron paramagnetic resonance (HF-EPR) are described. The DFT calculations on 2 support the (super 5)B(sub 1) electronic ground state predicted from the X-ray structure and a spin triplet first excited spin state was postulated to occur at low energy to describe the large value of the D parameter.

Abstract -- The sorption of palladium(II) from chloride solutions on polyacrylonitrile fiber filled with the AV-17 anion exchanger (PANF-AV-17) and its subsequent determination with p-nitrosodiethylaniline on the solid phase were [...]

Reporting easy access to a class of monodentate ferrocenyl phosphine ligands, which are effective for the Suzuki-Miyaura coupling of deactivated aryl chlorides including sterically hindered coupling samples. The electron-rich phosphines 1b have been demonstrated to be effective ligands for the palladium catalyzed Suzuki-Miyaura coupling of aryl chlorides.

A protein engineering study of the 102-residue protein U1A, which aggregates transiently in the wild-type form during refolding from the guanidinium chloride-denatured state, is carried out to analyze their nature. For the study, a series of mutants with increased aggregation tendencies is prepared by increasing the homology between two beta-strands of U1A and the Alzheimer peptide (beta-AP).

The tetramers of the group 11 (I) halides, M4X4 (M = Cu, Ag, or Au; X = F, Cl, Br, or I) and corresponding group 11 (I) phosphanes, chloride and bromide (XMPH3)4 (X = Cl or Br), are investigated by the density functional theory. It was found that all coinage metal(I) halide tetramers adopt squarelike ring structures with an out-of-plane distorted (butterfly) D(sub 2d) symmetry.

The development of an acylic chloride anion template in which the chloride anion is coordinatively unsaturated and available for subsequent complexation to various hydrogen bond donating components is described. This template orients a neutral hydrogen bond donating ligand and a pyridinium cation orthogonally to one another.

Use of Pd/P(t-Bu)(sub 3) as a versatile catalyst for Stille reactions is discussed. The method is user-friendly and provided general method for cross-couplings of aryl chlorides and for room-temperature couplings of aryl bromides.

Pulse electron-beam high-pressure mass spectrometer is utilized to estimate the gas-phase equilibria for clustering reactions of halide ions with methane and chloride ions with chloromethanes (CH(sub (4-m))Cl (sub m)). The irregular decrease in bond energies for F(super -)(CH4)(sub n) with n=6 and 8, for Cl(super -)(CH3Cl)(sub n) with n=2,4, and 6, and for Cl(super -)(CH2Cl2)(sub n) with n=2 and 4, reveal that the cluster are preferably solvated by the ligands with these n values.

Chlorinated methyl hydroperoxides, which are important, intermediates in the oxidation, combustion, and atmospheric photochemistry of chlorocarbons, is presented. The enthalpy values from reactions that are isodesmic reveal good agreement at all of the theory levels, suggesting effective cancellation of errors in the reaction sets.

The article presents a simple, palladium catalysed methodology, which can be used for the direct synthesis of arylboronic acids from the acorresponding aryl chlorides. The methodology for the conversion of these acids into useful boronates is also explained.

The reactions of HCl, P[Cl.sub.5], and a crown ether (12-crown-4 or 18-crown-6) in CH[Cl.sub.3] under anaerobic conditions have given complexes of the superacid HP[Cl.sub.6]: [H(12-crown-4)][P[Cl.sub.6]] and [H[(18-crown-6).sub.2]][P[Cl.sub.6]]. The crystal structures have shown that the proton is present in the center of the 12-crown-4-molecule in [H(12-crown-4)][P[Cl.sub.6]] whereas it lies roughly in the center of the 12-crown-4-molecules in [H[(18-crown-6).sub.6]][P[Cl.sub.6]].

Pd-catalyzed cross-couplings of the trichlorophenyl-, dichlorodiphenyl-, and chlorotriphenylgermanes with aryl bromides and iodides in the presence of tetrabutylammonium fluoride in toluene with addition of the measured amount of water is described. [Super 19]F NMR studies suggested that formation of the fluorophenylgermanes and the hypervalent germanate species as possible intermediates in the reaction with no haloligand required to be present on the Sn center, as tetraphenyltin efficiently transferred up to four phenyl groups during fluoride-promoted couplings with aryl halides.

Macrocyclization via an efficient high-yielding solid-phase intramolecular thioalkylation reaction is described. The reactions between the S-nucleophiles and newly generated N-terminal 4-chloromethyl thiazoles resulted in the desired macrocyclization products in high purities and good overall yields.

Structural characterization is developed to determine crystallographic site-specific metal disorder. Anomalous scattering at the Zn and Cu edges is used for determining that there is no Zn occupation of the intralayer Cu sites within the kagome layer, however there is Cu present on the Zn intersite, which has led to a structural formula of ([Zn.sub.0.85][Cu.sub.0.15])[Cu.sub.3][(OH).sub.6][Cl.sub.2].

The regioselective cross-coupling reaction of 2,6-dichloronicotinic acid and 2,5-dibromo-1,2,4-triazole derivatives were performed by using the carboxylic acid anion moiety as a tunable directing group. The reaction selectively produced the 2- or 6-substituted nicotinic acids, while only the 5-substituted triazoles were obtained under a variety of conditions.

A novel method is developed for the synthesis of 1,2-cis-2-amino glycosides via nickel-catalyzed [alpha]-selective glycosylation with C(2)-N-substituted benzylidene D-glucosamine and galactosamine trichloroacetimidates. The studies have shown that the presence of the substituted benzylidene functionality at the C(2)-amino position of glycosyl donors is very important for the high [alpha]-selectivity in the coupling products and the [alpha]-orientation of the C(1)-trichloroacetimidate group on glycosyl donors is required for the coupling process to occur.

Sodium dichloroisocyanurate was reacted with 1-amino-1,2,3-triazole to isolate 1,1' -azobis-1,2,3-triazole. The crystal structure properties and thermal stability and photochromic properties of the obtained triazole isolate is discussed.

The article presents a new nickel-catalyzed stereoconvergent approach, which can be used for the asymmetric Suzuki cross-couplings of the activated secondary alkyl electrophiles. The applicability of the methodology for the arylations of the racemic [alpha]-chloroamides is also analyzed.

A general and comprehensive approach is described for the preparation of complex aryl imidazoles, where all three C-H bonds of the imidazole core is arylated in a regioselective and sequential manner. The sequential C-arylation enabled by the SEM-switch has helped in producing a variety of mono-, di- and triarylimidazoles by using diverse bromo- and chloroarenes.

The monohydroxycalix[6]arene derivative is prepared by photochemical bromination of hexamethoxycalix[6]arene in aq THF. Monohydroxycalix[6]arene and its chloro derivative are useful synthetic intermediates for preparing structurally diverse calix[6]arenes functionalized at a single methylene bridge.

The article explains the synthesis, composition and properties of the various soluble chlorofullerenes [C.sub.60][Cl.sub.2,4,6,8,10]. The x-ray structure of the [C.sub.1]-[C.sub.60][Cl.sub.10] complex is also studied.

The dearomatization reaction of benzylic chlorides, chloromethylnaphthalenes, and naphthalene allyl chlorides with allenyltributyltin was performed in presence of Pd[(P[Ph.sub.3]).sub.4] catalyst at room temperature to yield the corresponding propargylated and/or allenylated dearomatization products. The reactions provide a new and efficient method for the synthesis of propargylic and allenic carbocycles.

A variety of meso-pyrimidinyl-substituted [A.sub.2]B- and [A.sub.3]-corroles (A = 4,6-dichloropyrimidin-5-yl) are prepared by optimization of the macrocyclization conditions. meso-Pyrimidinylcorroles have provided the advantage of an unprecedented broad scope of functionalization options.

A direct ruthenium-catalyzed radical chloroalkylation method was developed for N-acyl oxazolidinones capitalizing on valence tautomerism of titanium enolates. The chloroalkylation method provided a pathway for the enantioselective total synthesis of trichloroleucine-derived marine natural product neodysidenin.

Oligonucleotide containing 5-chlorouracil (ClU) paired opposite guanine (ClU-G) was constructed to gain insight into the reaction between hypochlorous acid (HOCl) from activated neutrophils at sites of inflammation and cytosine analogues which could generate multiple products. The electron-withdrawing 5-chloro substituent was found to facilitate ionization of the ClU N3 proton, promote mispair formation as well as render the glycosidic bond susceptible to base cleavage by DNA repair glycosylases.

The analysis of the J-based configuration analysis method in chlorinated hydrocarbons and chlorohydrins is described along with the development of a spectroscopic database that has facilitated the configurational assignment of these structures. Certain diastereomeric subclasses of 4,5-dichloro-2,3-epoxyhexane-1-ols have displayed a propensity to undergo ring-opening reactions at C-3 with concomitant inversion of configuration at the neighboring C-Cl at C4, implicating the intermediacy of chloronium ions.

N,N-Dialkyl-N-chloroamines are shown to be an effective source of electrophilic nitrogen for nickel-catalyzed coupling with diarylzinc reagents. Many N-chloroamines as well as organozinc reagents have reacted smoothly under the reaction conditions and a one-pot procedure is described that has circumvented the need to isolate the N-chloroamines.