I LITHIUM IODIDE

Li I LITHIUM IODIDE 41.903 2.8091E-02 6.6308E-14 -8.7334E-17 4.1888E-20 298 742 solid... 

Lithium hydride I lithium iodide C-Aminoethylation with aziridines... 

Boron fluoride I lithium iodide Ketones from a-halogenoketones 71. O... 

Lithium tetrahydridoaluminate I lithium iodide 5 11-1,3-Diol monoethers from p-alkoxyketones... 

Methyl esters react more rapidly with lithium iodide than do ethyl esters, which in turn react more rapidly than esters of secondary alcohols. On the other hand, i-butyl esters are cleaved very readily with a catalytic amount of lithium iodide. 

The cyclization of /erf-butyl alkoxyacetate 3 was studied in some detail105. The yields were acceptable but the selectivity was generally low, i.e., in the region of cis/trans 70 30. However, it is not very clear whether this ratio is dependent on the substrate, the solvent or on some additives (e.g., lithium chloride) and it is possible to raise the yield to 80% and the selectivity to 94 6 (entry 14) when /V./V -dimethylpropyleneurea (DMPU) is added to the solvent and lithium iodide (Lil) to the reaction mixture. To demonstrate the subtle and little understood differences in the reaction it is worthwhile pointing out entries 8 and 16, where good yields are obtained and the selectivity suddenly changes in favor of the trans-4 product. 

In one of the first studies, Yanagida et al.52 used a series of amphiphilic small molecules (Fig. 17.13) to obtain the gelation of an I / -based electrolyte composed by 0.6M l,2-dimethyl-3-propylimidazolium iodide, 0.1M lithium iodide, 0.1 M... 

Experimental evidence in support of this explanation is the fact that lithium added to a solution of lithium iodide in ethylenediamine dissolves without imparting a blue color to the solution—i.e., reacts immediately to give the amide. By contrast, lithium added to a solution of lithium chloride in ethylenediamine dissolves and imparts a deep blue color to the solution. The catalytic effect of iodide anion may be related to the effect of iodide anion on the electron spin resonance (ESR) absorption of solutions of alkali metals in liquid ammonia. Catterall and Symons (2) observed a drastic change in the presence of alkali iodides but very little change in the presence of alkali bromides or chlorides. They attributed this change to interaction of the solvated electron with the 6 p level of the iodide anion. 

In aqueous solutions of low concentration, when theories of ionic conductivities are applicable, no ion pairs will be formed in the case of the lithium and sodium halides at room temperature. Even in 13.9 mol (kg H20)"1 LiCl aqueous solution where the molar ratio of LiCl to H20 is 1 4, essentially no ion pairs between Li+ and Cl- ions are formed around 25°C, according to an MD simulation (28). Formation of the 1 1 ion pair between Li+ and Cl in aqueous solution is, however, concluded in 18.5 mol (kg H20) 1 aqueous solution where the nLiCI h2o molar ratio is 1 3, which is close to the saturation concentration of LiCl in water (29). Formation of the 1 1 Li+ Cl" ion pair has been suggested by a neutron diffraction method (30), but the data derived from such measurements were not in good agreement with the simulation results. No evidence has been found for ion-pair formation between Li+ and I ions at 20 and 50°C in 2.78 and 6.05 mol (kg H20) 1 aqueous lithium iodide using the solution X-ray diffraction method (31). 

Fig. 2.2. Cleavage of aromatic methyl ether using Sn2 reactions. In the dipolar aprotic solvent DMF, thiolate and chloride ions are particularly good nucleophiles for want of solvation through hydrogen bonding. In pyri-dinium hydrochloride a similar effect occurs because for each chloride only one N5 —H5 group is available for hydrogen bonding. The same increase in nucleophilicityin a dipolar aprotic solvent is used to cleave /i-ketomethyl esters with lithium iodide in DMF (cf. Figure 13.29).

The basic organometallic reaction cycle for the Rh/I catalyzed carbonylation of methyl acetate is the same as for methanol carbonylation. However some differences arise due to the absence of water in the anhydrous process. As described in Section 4.2.4, the Monsanto acetic acid process employs quite high water concentrations to maintain catalyst stability and activity, since at low water levels the catalyst tends to convert into an inactive Rh(III) form. An alternative strategy, employed in anhydrous methyl acetate carbonylation, is to use iodide salts as promoters/stabilizers. The Eastman process uses a substantial concentration of lithium iodide, whereas a quaternary ammonium iodide is used by BP in their combined acetic acid/anhydride process. The iodide salt is thought to aid catalysis by acting as an alternative source of iodide (in addition to HI) for activation of the methyl acetate substrate (Equation 17) ... 

The critical temperature for the thermal rearrangement of 3a under various conditions (in the melt,96 in quinoline20 or naphthalene17) appears to be in the vicinity of 180°. The 3-methoxy derivative (70) isomerizes readily with lithium iodide (in methyl ethyl ketone at 64°).17,96 When ethyl iodide is added to this reaction, i r-methylsaccharin (8) and iV-ethylsaccharin (22) are formed together.96 Lithium iodide catalysis is particularly useful in rearranging nucleoside derivatives, e.g., 71.17 The 3-benzyloxy derivative (73) reacts with debenzylation.17 Even more complex systems like derivatives of steroid alcohols17,20 are isomerized on heating in reasonable yields. When the optically active 3-(2-(cZ)octyloxy)benz[d]isothiazole-l, 1-dioxide was thermally re-... 

We present how to treat the polarization effect on the static and dynamic properties in molten lithium iodide (Lil). Iodide anion has the biggest polarizability among all the halogen anions and lithium cation has the smallest polarizability among all the alkaline metal cations. The mass ratio of I to Li is 18.3 and the ion size ratio is 3.6, so we expect the most drastic characteristic motion of ions is observed. The softness of the iodide ion was examined by modifying the repulsive term in the Born-Mayer-Huggins type potential function in the previous workL In the present work we consider the polarizability of iodide ion with the dipole rod method in which the dipole rod is put at the center of mass and we solve the Euler-Lagrange equation. This method is one type of Car-Parrinello method. 

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