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Everted membrane vesicles were prepared from cells of Pseudomonas aeruginosa, and cation/H+ antiport was measured. We observed activities of Na+/H+ antiport, Li+/H+ antiport and K+/H+ antiport. Judging from the competition pattern, it seems that there are at least two types of antiporter, a Na+(Li+)/H+ antiporter and a K+/H+ antiporter. Na+ was a good substrate for the Na+(Li+)/H+ system, whereas Li+ was a poor substrate. Although the K(m) value for Na+ (or Li+) was similar to those in Escherichia coli Na+/H+ antiporters, the Vmax value for Na+ (or Li+) was much smaller in the P. aeruginosa antiporter than in the E. coli antiporters. Growth of P. aeruginosa was strongly inhibited by 0.4 M LiCl, but not by NaCl or KCl.

Gutmann acceptor numbers have been determined using (31)P nuclear magnetic resonance (NMR) for AlCl(3)/EMIC melts as well as LiCl, NaCl, and KCl neutral buffered melts. In AlCl(3)/EMIC melts, where EMIC is 1-ethyl-3-methylimidazolium chloride, the change in Gutmann acceptor number as a function of the AlCl(3):EMIC melt ratio is attributed to an equilibrium between a monoadduct of triethylphosphine oxide.AlCl(3) and a diadduct of triethylphosphine oxide.2AlCl(3). Observed acceptor numbers for the neutral buffered melts appear linear with respect to the melt's initial mole ratio of AlCl(3):EMIC prior to buffering. The lithium cation appears to be the most Lewis acidic alkali metal cation followed by the sodium and potassium cations. Possible reasons for the change in acceptor number as a function of changing alkali metal cation concentration are presented.

Metal encapsulation into a cage and chemical modification on the outer surface of fullerenes endow them with some unique characteristic properties. Although the derivatization of endohedral fullerenes holds promise for producing novel new nano-carbon materials, there are few reports about such compounds. Herein, we report the synthesis of lithium encapsulated fullerenol Li+@C60O−(OH)7 using a fuming sulfuric acid method from [Li+@C60](PF6−) and characterization of its structure by IR, NMR, FAB mass spectroscopy, and elemental analysis. The hydroxylation of [Li+@C60](PF6−) is site-selective to preferentially give a single isomer (ca. 70%) with two minor isomers in marked contrast to the reaction of empty C60. We conclude from the analysis of radical species produced in the reaction of a C60 cage with fuming sulfuric acid that this unusual site-selective hydroxylation is caused by the lower HOMO level of Li+@C60 than that of empty C60. Furthermore, our results clearly indicate that the internal lithium cation is interacted with the introduced hydroxyl groups, and thus the properties of endohedral fullerenes can be controlled by the external modification of a fullerene cage.

In situ formed Li/Cl phosphinidenoid complexes [Li(12-crown-4)][M(CO)5(ClPC5Me5)] 3a-c (M = Cr, Mo, W) reacted with cyclobutanone (4), cyclopentanone (5) and cyclohexanone (6) in Et2O to yield the first P-C5Me5 substituted C(3)-spirofused oxaphosphirane complexes 7a-c, 8a and 9a,a'. In the case of cyclopentanone and 1a the outcome of the reaction in THF was different: here the formation of 8a along with (anionic) phosphinoate complexes 14a and 15a was observed, the latter possess an unusual ring-opened oxaphosphirane and 2-cyclopentylidenecyclopentanone as co-ligands to the lithium cation. NMR, IR and MS data as well as single-crystal X-ray structures in the case of 7a-c, 8a, 9a and 15a are reported. DFT calculations on the parent 1-oxa-2-phosphaspiro[2.n]alkane pentacarbonylchromium(0) complexes 10 (a: n = 2; b: n = 3; c: n = 4; d: n = 5) revealed that both ring strain energies and G(r) values decrease significantly as the spiroring size increases. This is caused by an increase in the exocyclic α bond angle at the oxaphosphirane C(3) atom, hence decreasing the s-character of the corresponding orbitals involved in endocyclic bonds at C(3) and thus becoming better suited for accommodation of small ring angles.

Reduction of corannulene and its simple alkyl derivatives with lithium metal gives tetraanions that come together to form ten-component aggregates with four lithium ions sandwiched between two decks of supercharged polycyclic aromatic hydrocarbons. Analogous species are not formed on reduction with sodium or potassium. Stereochemical and dynamic aspects of the new sandwich compounds have been studied by NMR spectroscopy (1A, 13C, and 7Li), and a simple picture for the “supramolecular bonding” is presented.

The title compound, Li[Ga(C12H27O3SSi)4], has been obtained as a by-product of the reaction of a metastable GaBr solution with (tBuO)3SiSLi. The asymmetric unit is composed of two separate mol­ecules. Each lithium cation is coordinated by two O atoms from butoxy groups of the ligand.

Three-dimensional macroporous tungsten trioxide (WO3) was electrochemically prepared by using the polystyrene opal as a template. The photonic stop band of the porous WO3 film could be changed when the WO3 was intercalated with lithium cation by the electrochemical method. The change of the stop band was attributed to the change of the refractive indices accompanied with the electrochromism of WO3.

The effect of alkali metal salts on the setting time of high aluminia cement (HAC) has been studied. The influence of concentration of the salts, chemical nature of anion and the type of alkali metal cation have been investigated. The results of the research indicate that alkali metal salts are set accelerators of HAC. The lithium cation has more effect on the setting time than other alkali cations because of its ability to form tetrahedral symmetry while the others will form the octahedral type. Lithium salts remove the nucleation barrier, caused by an initially fast precipitation. The influence of pH in mixing water is not important. The effect of hydroxyl group is greater than effect of other investigated anions due to the replacement leading to a further centre for oxobridge formation. The lithium salts cause decreasing of flexural and compressive strength of HAC mortars but also cause the strength development at early ages.

We investigate the lithium cation effects in high-performance dye-sensitized solar cells, which exhibit ∼10% efficiency and excellent thermal and light-soaking stability during 1000-h accelerated aging tests.

The title compound, [Li2(C18H22BO)2(C6H7N)2], is a lithium dimesitylboroxide dimer in which the lithium cation is also coordinated by one mol­ecule of 2-methyl­pyridine. At the core of the structure is an Li2O2 four-membered ring. The structure is centrosymmetric with an inversion centre midway between two Li atoms. Inter­molecular C—H⋯π inter­actions and π–π inter­actions between the 2-methyl­pyridine rings exist [centroid–centroid distance = 3.6312 (16) A].

CHEMISTRY Chemical bonds tend to form most easily by the attack of an ion on an oppositely polarized center, or by the neutral interactions of radical centers bearing unpaired electrons. Bisai et al. took the somewhat counterintuitive approach of preparing two negatively charged sites and then adding an oxidant to draw them together. The deprotonation of both a carbon and a nitrogen center came at a late stage in the synthesis of the polycyclic organic natural product lyconadin A. When more traditional approaches toward linking C and N to close the ring had failed, the authors relied on the likelihood that a lithium cation would stabilize a dianion through simultaneous coordination to both centers. Treatment with iodine then induced C-N bond formation in 80% yield, affording an impressive overall product yield of 10% over the 18 steps of the synthesis. — JSY J. Am. Chem. Soc . 130 , 10.1021/ja8028069 (2008).

Quasi-rings constructed as cyclic beta-ketoenol or lithium beta-ketoenolate moieties fused to aromatic molecules such as benzene, naphthalene and phenanthrene have geometric consequences for the conjoined aromatic similar to those caused by fusion of a benzene ring. This similarity is particularly marked in the case of lithium-bonded derivatives. Energies of bond separation reactions and the HOMA (harmonic-oscillator model of aromaticity) geometry-based index of pi-electron delocalisation show further similarities between quasi-rings and benzene. However, application of the ipsocentric approach to calculation of induced current density, shows that neither hydrogen nor lithium quasi-rings support pi-electron ring currents. It is argued that the geometric effects stem from electrostatic interaction of Li(+), and to a lesser extent H(+), with oxygen neighbours, causing a partial equalisation of CO bond lengths and knock-on effects on CC bonds, in the quasi-ring. The observed geometric effects do not arise from aromatic pi-electron delocalisation in the quasi-ring but are closer to the well-known push-pull effect between the electron-donating -OH and electron-accepting -CO groups, leading to reduction in bond-length alternation.

Electrochemical deposition and dissolution of metallic lithium in various phosphonium ionic liquids with bis(trifluoromethylsulfonyl)imide anion were evaluated by cyclic voltammetry using a Ni electrode. In the voltammograms measured in phosphonium ionic liquids containing 0.8 mol dm -3 lithium cation, cathodic and anodic peaks attributed to the deposition and dissolution of metallic lithium were observed at approximately -3.1 V vs Fc/Fc + . It was also found that phosphonium ionic liquids tended to give larger redox responses for the lithium deposition/dissolution than those of the corresponding ammonium ionic liquids.

This chapter is concerned with carbanions, which are, most simply, the conjugate bases (in the Bronsted sense), formed by deprotonation at carbon, of organic molecules. Carbanions may vary widely in stability, depending on the ability of substituent groups to delocalize negative charge. In the absence of substituents that are effective in delocalizing the charge, proton abstraction from a C-H bond is very difficult.

The title salt, [Li(H2O)4][Li(C7H5O2)2], which was synthesized by reacting equimolar quanti­ties of lithium hydroxide and tropolone in water, consists of a hydrated lithium cation whose charge is balanced by a ditropolonatolithate. Both Li atoms exist in a tetra­hedral geometry (the cation and anion lie on different sites of 222 symmetry). Hydrogen bonds link the cation and anion into a layer structure; π–π stacking [centroid–centroid distance 3.313 (2) A] is observed with the tropolonate rings, the stacking allowing the formation of channels that facilitate the packing of the cations within them.

The disiloxane O{SiMe2CH(SiMe3)2}2 is readily metallated by LiMe in thf (thf = tetrahydrofuran) to give the compound SiMe2C(SiMe)3LiC(SiMe3)2SiMe2OLi(thf)2, the crystal structure of which is reported.

Thermal properties and ion conductive characteristics of equimolar mixtures of zwitterion and lithium salts (Z/L mixtures) have been investigated. Through a systematic study of their structure–property relationship, we describe a zwitterion structure that produces high ionic conductivity when the zwitterion is mixed with lithium salt. We found that a pure zwitterion containing imide anion melted at 87 °C and the melting point of pure zwitterions was lowered in proportion to the alkyl spacer chain length between the anion and cation sites. In Z/L mixtures, ionic liquid-like domain formed between the cation sites of zwitterions and the anions of lithium salts regardless of the anion structure of the zwitterions. However, the anion structure affected the transference number of the lithium cation in the Z/L mixtures. To improve the thermal stability and the ionic conductivity of Z/L mixtures, suitable alkyl chain length between the cation and anion sites was determined to be 5 to 7 CH2 units.

Lithium cation assisted nucleophilic ring opening of cyclohexene oxide, by phenylacetonitrile carbanions, under phase-transfer conditions giving rise to a diastereoisomeric mixture of trans-γ-hydroxynitriles 7 and 8 is reported.

The present invention is a composition, a synthesis of the composition and a method of using the composition for selectively adsorptively separating nitrogen from oxygen wherein the composition is a crystalline EMT with a Si/Al ratio less than 2.0 and a micropore volume determined in the sodium and/or potassium form of at least 0.20 cm 3 /g and a lithium cation exchange of at least 80%, preferably including an intergrowth with a crystalline FAU structure, wherein the pure or intergrowth compositions have the chemical formula: M.sub.2/n O:X.sub.2 O.sub.3 :(2.0 to

Phospate diesters, 2a, 2b and 2c, having p-tert-butylcalix[4]arenes and alkyl groups as ester moieties exist as an equilibrium of cone and partial-cone conformations in solution and selectively transport Li+; however, the conformations of the calix[4]arene moieties in the Li and Na complexes of 2a as the methyl ester and/or 2b as the ethyl ester in solution are cone only, although that of the K complex exists as a mixture of cone and partial-cone conformers.

Tertiary 1-naphthamides racemise much more slowly than their laterally lithiated derivatives, and the relative rates of racemisation and epimerisation of these derivatives indicate that the lithium-bearing stereogenic centre inverts via a "conducted tour" mechanism, in which the lithium cation is delivered from one face to the other by coordination to the rotating amide group.

Summary form only given. The lithium cation doping on the surface of polyacene semiconductor (PAS) molecule has been investigated by using quantum chemistry MNDO and CNDO/2 methods. There are two stable adsorption sites for Li over the central sites of C=C bonds and benzene ring group of PAS. The calculation of EHMO-CO energy band structures indicates: after lithium is adsorpted at the hole site on the surface of PAS, the energy gap of system decreases.

In a series of experiments the appearance of lithium cation in plasma following ingestion or intravenous administration of lithium salts was measured in order to examine the suitability of lithium as a marker of supplement intake by cattle. In experiment 1, cattle were offered low quality hay ad libitum and 0.15, 0.4, 1.0 and 3.0 kg cottonseed meal (CSM) supplement per day. Following ingestion of lithium-labelled CSM, the lithium concentration in plasma reached a maximum after about 24 h and the subsequent decrease in concentration appeared to follow a single exponential relationship. The rate constant of this disappearance of lithium from plasma was greater (P

We report the synthesis of a class of lithium salts in which the two strongly Lewis basic sites of lithium imidazolide are each complexed by the Lewis acid to yield lithium bis(trifluoroborane)imidazolide The anion has a high degree of charge delocalization over the aromatic ring and two four-coordinate boron centers and has only very weakly basic sites on the periphery which keep the coordinating ability to the lithium cation low. The salt has a conductivity of 5.06 mS/cm in 1:3 ethylene carbonate:ethylmethyl carbonate solution and has high oxidative stability. Lithium cells made with common anode and cathode materials using an electrolyte containing this salt had performance similar to cells using an electrolyte containing © 2003 The Electrochemical Society. All rights reserved.

An experimental and computational investigation of the structures and vibrational frequencies of N,N′-dimethylethylenediamine–lithium triflate (DMEDA–LiTf; Tf – = CF 3 SO 3 – ) has been done using a combination of hybrid Hartree–Fock/density functional calculations and Raman and IR spectroscopy. Band assignments for DMEDA–LiBr were made by comparing the experimental Raman and IR spectra of a 5 ∶ 1 DMEDA–LiBr sample with the calculated vibrational frequencies of the DMEDA–Li + and DMEDA–LiBr complexes. Band assignments for DMEDA–LiTf were made by comparing the experimental spectra of samples over a composition range of 20 ∶ 1 to 1.5 ∶ 1 with calculations done on the DMEDA–LiTf complexes. The effect of the lithium cation and lithium triflate on the geometries and vibrational frequencies of the DMEDA will be examined. The combined experimental data and computational results clearly show that the intramolecular hydrogen bonding in pure DMEDA is broken upon addition of lithium bromide or lithium triflate.

The gas-phase lithium cation basicities (LCBs) of the six amides RC(O)NRR' (R, R' = H or Me) were reexamined by means of Fourier transform ion cyclotron resonance mass spectrometry and using the kinetic method. LCBs for HCONH2, MeCONH2 and MeCONHMe were reevaluated. The new set of experimental data was found to be consistent with the expected methyl-substitution effects. For a series of compounds including the six amides and H2CO, MeCHO and Me2CO, density functional theory calculations of LCBs and gas-phase proton basicities (GBs) at the B3LYP level reproduce satisfactorily the trend of substitution effects.

A solid ion conductor material is made from branched polyethylene imine and a lithium cation salt in such a manner that the ratio of the number of nitrogen atoms contained in the polymer to the number of lithium cations originating from the salt is optimized. The branched polyethylene imine can be plasticized within a certain proportionate range of plasticizer. This type of material is used as electrolyte, notably in electrochromic systems.

Dibenzo[b,g]chrysene dianion (32–) shows in its NMR spectrum a partitioning of charge. In the dianion most of the charge is located on the ‘anthracene’ moiety. These observations have been confirmed by MNDO calculations. In the calculations, the location of the lithium cation is taken into account. This unusual phenomenon is connected with the system's paratropicity and with its charge alternation. The NMR assignments were assisted by 2D techniques.

The synthesis of several macrocycles containing two bipyrazolic subunits, with different cavity sizes and with donor-group-bearing side arms attached, is reported. Their alkali cation binding ability has been studied from two aspects : extraction and transport through an artificial liquid membrane. Macrocycles described here show a high selectivity towards Li + and Na + cations; furthermore one of them is remarkably well adapted to extract selectively and to transport efficiently the lithium cation in competitive conditions.

Added lithium cation has no effect on the stereochemical outcome of the displacement of chloride or p-nitrophenoxide from phosphorus in acyclic and some cyclic molecules. In other cyclic systems th...

Reaction of phosphononitrile 2 with a series of a-enones in THF- n -BuLi gives different results according to the enone nature. C 4 -disubstituted enones are attacked at the carbonyl carbon; phenones and cyclopentenone are attacked at the double bond (except dypnone); benzalacetone, 3-penten-2-one and cyclo-hexenone give mixtures of C 2 and C 4 substituted products. Electrophilic assistance by complexation of the lithium cation by α-enone can be shown except for phenones.

The effect of lithium chloride on the relaxation mechanisms of simple acid and alcohols has been examined. Dipolar relaxation is predominant for acetic acid and ethanol. Lithium chloride (approximately 10%) significantly increases the rate of dipolar relaxation for all carbons and protons of acetic acid, probably through an increase in aggregate size or viscosity. Lithium chloride (approximately 1.5%) has a similar but smaller effect on the protons of ethanol. The methyl carbons and fluorines of trifluoroacetic acid and 2,2,2-trifluoroethanol relax primarily by spin-rotation. With about 10% lithium chloride, dipolar relaxation becomes more important for trifluoroacetic acid. With about 1.5% lithium chloride, trifluoroethanol possibly shows an enhancement of spin-rotation relaxation for the CF3 nuclei.

Cis lithium thioenolates are preferentially formed by deprotonation of dithiopropanoates with lithium diisopropylamide in tetrahydro-furan at -78°C. The cis selectivity observed, is unproved by increasing the alkylthio group size or by the ability of this group to chelate the lithium cation. When more bulkier bases such as lithium 2,2,6,6-tetramethylpiperi-dide or lithium hexamethyldisilazane are used, the selectivity is lowered. This lowering of selectivity is suppressed when the deprotonation is performed in presence of 12-crown-4. Addition of hexamethyl phosphoramide to the base does not invert the selectivity as it uas reported for the deprotonation of esters ; a rather better cis selectivity is reached in the case of methoxymethyl dithiopropanoate. These original results are well understood in terms of an open transition state model. Preformed lithium thioenolates are reacted uith a variety of aldehydes and afford stereo-specifically syn aldols. The influence of hexamethylphosphoramide and reaction time is also examined.

Under certain conditions the interface between an aqueous phase and an organic phase (ITIES, interface of two immiscible electrolyte solutions) has certain properties analogous to a metal/electrolyte-solution interface. By polarization of the ITIES using potential-sweep voltammetry reproducible voltammograms corresponding to ion transfer across the ITIES are obtained. In the presence of cation-complexing ionophores in the organic phase cation transfer is facilitated. The acidic form HX of carboxylic ionophores, monensin A and B, acts in the nitrobenzene/water system as a sodium carrier while the complex of its anion with sodium or lithium cation (M+) is a proton carrier. The equilibrium constants of the reactions M++ HX ⇌ MHX+ and MX + H+⇌ MHX+ have been determined from the voltammograms. The stabilities of the complexes correspond to the series Li+ > Na+≫ K+. The substitution of methyl (monensin B) for ethyl (monensin A) on ring C increases the stability of the sodium complex by ca. 1 kJ mol–1 and has no effect on the acidity of the carboxy group.

Solvation energies of lithium first-row compounds LiX (X H, Li, BeH, BH2, CH3, NH2, OH, F) and of the lithium cation with the model solvents, water and ammonia, have been calculated ab inito (MP2/6-31 + G*//6-31G* with zero-point vibrational energy corrections at 3-21G//3-21G). The solvation energies are found to be remarkably constant: −18.0 ± 1.2 and −21.5 ± 1.3 kcal/mol for the hydrates and ammonia solvates, respectively. This independence on the nature of X is due largely to the ionic character of the LiX compounds (dipole moments 4.7–6.6 debye). The unexpectedly high solvation energies of the lithium molecule (−14.3 and −17.8 kcal/mol, respectively) are due to the polarizability of Li2. At the same level, the lithium cation has interaction energies with H2O and NH3 of −34.1 and −39.7 kcal/mol, respectively. For the hydrates of LiOH and LiF cyclic structures with hydrogen bonds and somewhat increased solvation energies also are described.

Basis set expansion and correlation effects on computed lithium cation affinities have been evaluated for the oxygen and nitrogen bases CH3OH, H2CO, CO, CH3NH2, CH2NH, and HCN. The presence of diffuse functions on nonhydrogen atoms is found to be the most important single enhancement of double- and triple-split valence plus polarization basis sets. With the triple-split basis, enhancement effects are nearly additive. Correlation usually decreases computed lithium ion affinities, with the second order Moller-Plesset correlation term being the dominant term.

A new series of 4-substituted derivatives of dibenzo-14-crown-4 including 4-nitro-DB14-crown-4 (2a), 4-bromo-DB14-crown-4 (2b), 4-chloro-DB14-crown-4 (2c) and 4-formyl-DB14-crown-4 (2d) has been synthesized with and without a lithium cation template. No matter with or without the template, a satisfactory correlation between the nature of the substituent group on the benzene ring and the reaction yield is observed. The larger σ values for the substituent groups gave lower yields.

The CHF-PT-EB-CNDO method has been used to compute the polarisability and second hyperpolarisability of the hydrated lithium cation with one and two hydration shells. The effect of the Li+… (H2O)n interaction on these properties is discussed and the main findings are confirmed in hydrated Na+, Be2+, and Al3+.

C-13 NMR data for a series of stabilized and unstabilized ylides indicate flattening at the ylidic carbon with respect to the parent salts. For unstabilized ylides association between the carbanionic center and the lithium cation cannot be neglected.

The review considers questions concerning the synthesis and complex-forming capacity of macrocyclic compounds containing in the ring phosphorus atoms with different degrees of coordination (from three to five) as well as macroheterocycles with phosphorus-containing side chains (lariat compounds). The introduction of the phosphoryl group into the macrocycle lowers the stability of the complexes of the macrocyclic compounds with alkali metals and reduces the selectivity compared with the analogous crown-ethers. Only the lithium cation in the case of macrocyclic phosphine oxides is an exception. Lariat macrocycles are promising: the phosphorus fragment ensures the effective additional binding of the cation imparting a high stability to the complex. The bibliography includes 191 references.

The complex of benzophenone-lithium pentaiodide crystallizes in space group PI (Z = 2). The unit cell dimensions at 100 K are a = 9.605(5), b = 14.911(3), c = 18.248(4) A, α = 102.35(2), β = 103.45(3) and γ = 91.32(3)[ddot]. The crystal structure consists of infinite columns of I5 molecules each of which is bent at the central iodine atom with an I–I–I angle of 105[ddot]. The pentaiodides are stacked such that one branch of each molecule participates in the column formation, while the second branch forms a two-atom side chain. Neighboring columns of pentaiodides are anti-parallel to each other. The columns of pentaiodide molecules are surrounded by the host benzophenone molecules. Each lithium cation is tetrahedrally coordinated to four oxygens of the benzophenone molecules. A refinement of the occupancy of the iodine atoms gives an iodine deficiency of 7%, equally distributed over all iodine positions. The result is supported by the elemental analysis and the measurements of the density of the c...

A layered double hydroxide with a chemical composition (A12Li(OH)6)+X �9 nH20, where X is an interlayer anion, has been synthesized hydrothermally at 130~ from aluminum-tri-(sec-butoxide) and lith- ium carbonate. Electron micrographs showed the product to have a platy morphology with distinct hex- agonal symmetry, which has been corroborated by selected area electron diffraction patterns corresponding to a projection of the structure on its (001) plane. Evidence for a superlattice with a = 5.32/~ was obtained, indicating cation ordering among octahedral sites. X-ray powder diffraction data also can be interpreted by reference to a hexagonal supercell with dimensions a = 5.32/~ and c = 15.24/~. The arrangement of the octahedral sites appears to be that of gibbsite, but with the vacancies filled with lithium cations. Anions must be present between the sheets to balance the charge. A complete assignment of the observed infrared lattice vibrations can be made for the anion (AlzLiOt) with the ideal D3d symmetry for motions within one octahedral sheet. The results show that (A12Li(OH)tl+X -- nH20 is a hydrotalcite-like compound with the octahedral cations largely ordered. The general formula for hydrotalcite-like compounds, (M2+i_xM3+x(OH)2)x+xm-x/m. nH20, should be extended to include the monovalent lithium cation.

In order to investigate the structure of solvation of the lithium cation, the authors obtained the far-infrared spectra and calculated the spectral maxima for solutions of LiCl, LiBr, LiI, LiBF/sub 4/, and LiClO/sub 4/ in dimethyl sulfoxide at 298 and 110 K. The calculations and the experiments are in qualitative agreement. These results suggest that lithium is associated with five molecules of Me/sub 2/SO which conform to a trigonal bipyramid as a structure of primary solvation; an anion is associated with the solvated cation. 16 references, 2 figures, 4 tables.

Nonexponentiality of the nuclear quadrupole relaxation of spin - 3 2 was carefully examined for the nonextreme narrowing case. Two decay constants for 7 Li longitudinal relaxation in 11 M aqueous solution (D 2 O) of LiCI were determined. The ratio of two decay constants is interpreted on the basis of anisotropic reorientational motions of a hydration complex of lithium cation.

The local structure of the solvated lithium cation in ethylene carbonate (EC) solutions has been investigated using Raman spectroscopy. The relative intensity change of the split Raman line at ∼ 900 cm−1 in LiClO4/EC was treated quantitatively. This splitting originates from the coexistence of two type EC molecules; one solvates to Li cation and the other does not solvate to Li cation. The resultant intensity data have been applied to the analysis of the Li+-EC solution. The possibilities of the determination of the degree of dissociation of LiClO4 and that of the solvation number of Li+ in a contact ion pair were also discussed. It was found that this Raman line is useful for analysing the solution structure in Li+-EC systems. Basic intensity parameters for such analyses can be determined.

Summary The electrochemical synthesis of cis -1,2-diphenyl-1,2-cyclopentanediol by reduction of 1,3-dibenzoylpropane in acetonitrile is described. The intramolecular pinacolization has been studied using polarography, coulometry, cyclic and linear sweep voltammetry. The variations of the peak potential with the sweep rate, the initial concentration, the amounts of water and lithium cation added have been the main basis of the kinetic analysis of the cyclization mechanism. It is shown that the mechanism involves the formation of the open chain dianion from disproportionation of the initial anion-radical and that the cyclization step itself is an internal radical-radical coupling in the dianion.