Lithium carbonate interaction

Table 12. Interaction temperatures in systems containing lithium carbonate (after Agulyansky et al. [93]).

The other structures all represent cases in which the Group IV element is interacting with 3 lithium atoms, and in each case a three-dimensional lithium aggregate is formed. The lithium-lithium and lithium-carbon distances are summarized in Table VIII for those structures that have been determined. In addition, lithium-carbon distances in several lithium-aromatic ion pair systems are included in Table VIII for comparison (18, 19), as well as the observed distances in the hexamer of trimethylsilyllithium. In the dimeric molecule, the Li—Li distance of... 

These theoretical studies were given real credibility when Hoffmann and Rolle showed that the lithium carbon-carbon double-bond interaction can be observed by heteronuclear coupling in the NMR spectrum of 5-hexenyllithium25. 

O Regan JB. Letter Adverse interaction of lithium carbonate and methyldopa. Can Med Assoc J 1976 115(5) 385-6. 

Walbridge DG, Bazire SR. An interaction between lithium carbonate and piroxicam presenting as lithium toxicity. Br J Psychiatry 1985 147 206-7. 

Lithium iodide, Lil.—On evaporation of the solution obtained by the interaction of lithium carbonate and hydriodic acid, or barium or calcium iodide, lithium iodide crystallizes in the form of hydrates,7 a trihydrate, dihydrate, and monohydrate having been isolated. Above 300° C. the anhydrous salt is formed, but its action on glass and porcelain at high temperatures has prevented its preparation in the pure state. The boiling-point of the iodide is 1170° C.,8 and the vapour-pressure in atmospheres corresponds with the expression... 

The anhydrous metaborate, LiB02, is precipitated by the interaction of alcoholic solutions of a lithium salt and boric acid,2 and can also be obtained by fusing lithium carbonate with boric acid.3 It forms triclinic leaflets of pearl-like lustre, and melts 4 at 843s C. Boiling with water converts it into the octahydrate. 

Theoretical calculations of organolithium species have received considerable attention. The low atomic number of lithium is suitable for the most sophisticated molecular orbital methods. Although much debate exists over the degree of covalency within lithium carbon-bonding interactions, the presence of some covalent character in Li bonds of alkyllithinm componnds is widely accepted. 

Allyllithium. The highest occupied allyllithium molecular orbital, shown in 25a, is composed of the allyl highest occupied molecular orbital, (HOMO) and a vacant p orbital on lithium. This interaction is favored when lithium adopts the bridging position indicated by NMR studies (39). (The available allyllithium X-ray structure is that of a polymer (40), but it may be possible with suitable lithium ligands to obtain the monomer.) The alternative ion pair formation (25b) would also place the lithium cation equidistant between the two negatively charged carbon centers at C(l) and C(3). 

The monomeric LiAl [N=C(f-Bu)2]4 (78) 102) is unique in that the lithium-carbon [or Li—H—C (79)] interactions involve hydrocarbon moieties which are removed from the other metal. That is, the carbon atom is not serving as a bridge between metal atoms. In addition, the lithium atom in this complex has a tetragonal-planar (rather than tetrahedral) environment. 

Recently, we were able to show that lithium organyls are also able to interact with CO [6] in a newly developed LXe cell constructed from one piece of single crystal silicon [7]. In a first step carbon monoxide is complexed by back-bonding to BuLi (n(CO) 2047 cm ) and inserts in a second step at higher temperature into the lithium-carbon bond (n(CO) 1635 cm ). Further... 

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