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In water capillary zone electrophoresis cannot be used to investigate basic compounds, which are so weak that their [pK.sub.a,HB+] values are less than zero. In acetonitrile the basic strength of such compounds is increased by many orders of magnitude. Accordingly, several extremely weak bases are protonated at low pH in acetonitrile, thus, allowing their investigation by CZE. In this work the CZE separation of thioacetamide, acetamide, thiourea, benzamide, and 4-nitrobenzamide as well as that of N-methylformamide, N,N-dimethylformamide, formamide, and dimethyl sulfoxide is demonstrated in acetonitrile using 10 mmol/L perchloric acid as an electrolyte. The effect of BGE additives, like water and acetic acid, on the CZE performance is discussed. The problem of finding a suitable electroosmotic flow marker at low pH in acetonitrile is addressed, and nitromethane is shown to be a proper marker compound under such extreme conditions. This work demonstrates how organic solvents can enlarge the field of application of CZE.

Solvation of ligands in one medium relative to another is analyzed from standard transfer Gibbs energies using acetonitrile as the reference solvent. It is concluded that the extent of complexation of macrocycles with soft metal cations is controlled not only by solvation changes that the free cation undergoes in moving from one medium to another but also those for the ligand and its complex cation in these solvents.

The {Fe(super IV)(Mu-O)(Mu-caboxylato)2Fe(super III)}(super 3+) core represents an important new structural motif in the coordination chemistry of high valent non-heme diiron compounds. Through the successful calculation of the spectroscopic parameters of 4(super ox) and 5(super ox), it is claimed that the calculated structures of these species are realistic and their electronic structure is described qualitatively by the DFT methods.

The hybrid materials constituted by polypyrrole doped with the polyoxometalate (POM) anion [SiCr(H2O)W11O39](super 5-) are electrogenerated from acetonitrile solutions. The electrochemical behavior of the hybrid films is studied by cyclic voltammetry in three different electrolytes formed by two anions and two cations dissolved in acetonitrile.

A study was conducted to demonstrate that the band gaps of (n,m)SWNTs (single-walled carbon nanotubes) are strongly affected by the change in microdielectric environments around the isolated nanotubes. A strong solvent dependence of the electrochemical band gaps due to the difference in the solvation energy of the charged SWNTs produced during the electrochemical processes provided better insight into the essential electronic properties of the carbon nanotubes.

Rhodium-catalyzed regioselective arylzincation of terminal allenes is performed to obtain synthetically useful functionalized allylzinc reagents. The obtained allylzinc reagents react with a variety of electrophiles such as acetonitrile to offer a more versatile three-component coupling reaction.

A study was conducted to determine the thermodynamic driving forces of the phenothiazines and their analogues to release hydride anion, hydrogen atom, proton and electron. The data obtained on the chemical thermodynamics on the mutual conversions between phenothiazines and their various reaction intermediates in solution could be used to promote the fast development of the chemistry and application of phenothiazines and their analogues.

An efficient approach to synthesize 1-arylmethyl-2-(bromomethyl)aziridines into 2-(2-cyanoethyl)aziridines by reaction with [alpha]-lithiated trimethylsilylacetonitrile in THF is described. This aziridines could serve as substrates for the preparation of a variety of aminonitrile derivatives via elaboration of the aziridine moiety.

The simulations of a model system of charged spherical ions in the ionic liquids dimethylimidazolium chloride ([dmim][Cl]), dimethylimidazolium hexafluorophosphate ([dmim][P[F.sub.6]]) and the polar liquid acetonitrile (MeCN) are used for examining the applicability of Marcus theory to electrochemical half-cell redox processes in these liquids. The similarities between the different types of solvent are attributed to the essentially long-range nature of the relevant interactions and the effectiveness of the screening of the ion potential.

A synthetic route of potentially wide scope for the organoimido functionalization of polyoxotungstates is demonstrated by the reaction between the monovacant lacunary polyoxotungstate, [alpha]-([(n-[C.sub.4][H.sub.9]).sub.4][H.sub.3][P[W.sub.11][O.sub.39] and W(N[C.sub.5[H.sub.5])[Cl.sub.4] in anhydrous acetonitrile.

The sulfinyl group mediated stereoselective quarternization of [alpha]-amino phenylacetonitriles is being described in the analysis. The remote sulfinyl group exerts complete stereoselective control in the reaction, hence forming the benzyllithium intermediates.

The kinetics and mechanism of the reactions of aryl phenyl chlorothiophosphates and aryl 4-chlorophenyl chlorothiophosphates with substituted anilines in acetonitrile are described. The cross-interaction constant and primary kinetic isotope effects are used for proposing a concerted [S.sub.N]2 mechanism with front- and back-side nucleophilic attack on substrate.

The electrostatic interactions in liquid acetonitrile are described using a discrete model based on the multipolar expansion including terms up to hexadecapoles. It is found that the permanent local field is dominated by the dipole-dipole interactions although the contribution of the higher multipoles is not negligible for accurate predictions.

The electrochemical reduction of 3,5-di-tert-butyl-1,2-benzoquinone is studied in acetonitrile with added 2,2,2-trifluoroethanol. The only mechanism that could be found which would account for all the data involves proton transfer to [Q.sup..-] occuring within a higher complex, [Q.sup..-](HA)3.

The influence of lithium ion pairing on the voltammetric reduction of anthraquinone in acetonitrile is discussed. The effect of lithium pairing is also demonstrated for the case in which 1-anthraquinonyl groups are covalently attached to multiwalled carbon nanotubes abrasively immobilized on a basal plane pyrolytic graphite electrode.

A combination of different approaches is used to present an investigation of time-dependent solvation phenomenon. Quantum mechanical (QM) calculations of the solute electronic structure are performed in the presence of the solvent and used to study the S(sub 0) -> S(sub 1) transition and to provide the parameters that are used for the molecular dynamics (MD) simulation of solvation dynamics.

Theoretical investigations were performed on the electronic singlet and triplet transition energies of 2-thiouracil, 4-thiouracil, 2,4-dithiouracil, and their methyl derivatives in the gas phase and in water and acetronitrile solutions. The computed results were compared with corresponding properties of uracil.

The two-photon ionization of stilbene dendrimers having stilbene core and benzyl ether type dendrons is studied in an acetonitrile and 1,2-dichloroethane mixture (3:1) in order to elucidate the dendrimer effects. The results suggest that the dendron is an effective shield of the stilbene core radical cation against the chloride ion.

Chemically induced dynamic nuclear polarization (CIDNP) effects in the sensitized photoreactions of triethylamine DH are investigated in a series of aprotic solvents of widely varying relative permittivity [member of], including mixtures of acetonitrile and chloroform. A theory of pair substitution taking place solely during encounters of the radicals is presented.

The thermodynamics of anion complexation of calix[4] pyrrole and halide anions (fluoride, chloride and bromide) in acetonitrile and N, N- dimethylformamide at 298.15 K are discussed. The results show that calix[4]pyrrole is able to recognize selectively the halide anions in these solvents.

The surface-enhanced Raman scattering (SERS) from the platinum-acetonitrile interface in the presence of iodide, the lithium cation, water, and pyridine was analyzed as a function of applied potential. It was found that the typical Raman band of cyanide species by the dissociation of the solvent acetonitrile upon adsorption onto highly roughened platinum electrode surfaces was detectable for all of the systems.

The solution-phase voltammetry of the modular podand 1,3,5-tris(3-((ferrocenylmethyl)amino)pyridiniumyl)-2,4,6-triethylbenzene hexafluorophospahte, [Pd][PF6](sub 3), in acetonitrile and ionic liquids exhibited a well-defined diffusion-controlled process at a potential of about 1.40 V vs [Co(Nu5-C5H5)(sub 2)](super +/0). The voltammetry of very slowly dissolving microparticles of [Pd][PF6](sub 3) mechanically attached to an electrode surface in contact with ionic liquids was indistinguishable from that observed when the podand was in the dissolved state in the ionic liquid.

Electron localization in liquid acetonitrile is studied. The following condition of electron localization in liquid acetonitrile is found: there are two solvent anions, a stable dimer radical anion (anion-2) that absorbs in the visible and a metastable multimer radical anion (anion-1) that absorbs in the IR.

The investigation on the covalent binding and structure of acetonitrile on Si(111)-7 * 7 is done to provide information on the interaction of pi-electrons of the C triple bond N group with the dangling bonds of Si(111)-7 * 7. The density functional theory (DFT) calculation results and all the experimental evidence revealed that functional organic monolayer of acetonitrile on Si(111)-7 * 7 are formed through a di-sigma binding mechanism involving the coupling of one pi(sub CN) bond with an adatom-rest atom pair at the interface.

The acetonitrile molecules in HY zeolite by a combination of the molecular dynamics technique and the electonegativity equalization method were studied. The results of the MD simulations show that the interaction of the molecule with the OH groups strongly influences the equilibrium geometry of the zeolite hydroxyls.

Sum frequency generation (SFG) vibrational spectroscopy is used to investigate the orientation of acetonitrile (CH3CN) and Pt (111) electrode. The SFG results indicate that acetronitrile orients in response to the electrode potential with the C-C bond, C3 symmetry axis, perpendicular to the surface.

Rate constants for quenching by molecular oxygen of excited single and triple states are examined, and are reported for 12 aromatic hydrocarbons in acetonitrile. It is concluded that the logarithm of the net rate constants for quenching the triplet states without energy transfer to oxygen for 11 of the aromatic hydrocarbons which show a linear dependence on the free energy for full charge transfer from the triple state.