The self-diffusion coefficients of the lithium ion, the anion, and the solvent in lithium bis(trifluromethanesulfonyl)imide (LiTFSI, LiN(SO2CF3)2) solvent systems were measured using the pulse-gradient spin-echo (PGSE) NMR method. Fourteen different organic solvents that are commonly used as organic solution electrolytes in lithium batteries were studied. The self-diffusion coefficients of the corresponding pure solvents were also measured. Since a good correlation between the self-diffusion coefficients of the pure solvents and the inverse of the viscosity was obtained, the results are discussed in terms of the Stokes-Einstein equation. Comparisons of the self-diffusion coefficients of the solvent, the lithium ion, and the anion (TFSI ion) illustrate the solvation behavior for each solvent. The relationship between the ionic conductivity and the sum of the diffusion coefficients of the lithium ion and the anion gives the degree of ion-pair formation and permits the roles of the solvents in the electrolytes to be clearly explained.

One-bond isotope shifts of 35C1/37CI natural abundance chlorine isotopomers were measured in the 75.4 MHz "C NMR spectra of a series of para-substituted chlorobenzenes. The high-field isotope shift effect 1A13C(37CI) was established from the relationship between the chlorine isotopomeric ratio and the carbon peak intensities. It was found that the 1A13C(37CI) values are in the range of -4.0 to -5.2 ppb. The isotope shifts tend to decrease as the electron-attracting character of the substituent increases, providing a linear correlation between the isotope shift and the chemical shift of the chlorine-bearing carbon.

2,3-Dihydro-3-[(S)-1-phenethyl]quinazolinone and some new 2-substituted derivatives bearing isopropyl, o-nitrophenyl and p-nitrophenyl groups were prepared in 40-90% yield by amidation of isatoic anhydride with (S)-phenylethylamine, followed by condensation with triethyl orthoformate, isopropylaldehyde, o-nitro-and p-nitrobenzaldehyde, respectively. The two 2-subtituted dihydroquinazolinones obtained either by using isopropylaldehyde, o-nitro-or p-nitrobenzaldehyde, were separated and purified before their NMR spectra in CDCl 3 solutions were recorded. The detection of the low energy conformation of O=C-N-phenethyl segment in solution allowed the correlation of the NMR data with the configuration of newly stereogenic carbon C-2; thus, one diastereomer was labeled SS while the other was RS. Configurations determined by the NMR method were corroborated by X-ray diffraction analysis. X-ray structures of each diastereomeric series showed characteristic conformational types: a propeller-like for the SS and a hairpin for the RS series. Interatomic distances of the hairpin conformation suggest the existence of intramolecular face-to-face interactions between two aromatic rings. Molecules 2007, 12 174

Absolute gas-phase acidities Delta(acid)G(0)(OH) and Delta(acid)G(0)(CH) were calculated at the B3LYP and MP2 levels using six different standard basis sets for the OH and CH heterolytic bond cleavage of ethanol and twelve derivatives of the type CH(3-n)F(n)CHX(r)OH, where n ranges from zero to three and represents the number of fluorine atoms and r represents hydrogen and the type of aromatic ring, namely: X(0) = hydrogen, X(1) = phenyl, X(2) = 1-naphthyl, and X(3) = 9-anthryl. The similarity between calculated and experimental Delta(acid)G(0)(OH) values for ethanol (1a), 2-fluoroethanol (1b), 2,2-difluoroethanol (1c), 2,2,2-trifluoroethanol (1d), and 1-phenylethanol (2a) was used to validate the right theoretical method for this study. Substituent partial contributions to hydroxyl-, methylene-, and methine-hydrogen acidities were evaluated by linear combination. Good parameter fittings of the primary and secondary alcohols were obtained and interpreted as additive contribution of the substituent effects. The nonlinear contributions were identified. Calculations prove that fluoroalcohols exhibit C-H acidity, which is usually lower than O-H acidity. In principle, the inversion of this acidity order is possible by the introduction of a large aromatic ring instead to increase the number of fluorine atoms.

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