Oxygen lithium salt

Compare atomic charges for the enolate anion and the lithium salt. Are there major differences, in particular, for the oxygen and the a carbon Also compare the highest-occupied molecular orbital (HOMO) in the two molecules. This identifies the most nucleophilic sites, that is, the most likely sites for attack by electrophiles. Are the two orbitals similar or do they differ substantially Elaborate. 

Zirconium reduces almost all oxygen-containing salts. This is the case for alkali hydroxides (accidents with the lithium, sodium and potassium compounds) and zirconium hydroxide, lithium, sodium and potassium carbonates, alkaline sulphates sodium tetraborate and copper (II) oxide. This is true especially for oxidising salts such as alkaline chromates and dichromates, chlorates (accident with potassium salt) and nitrates (accident with potassium salt). 

Since the lithium salt rearranges faster than the potassium salt in this rearrangement from oxygen to carbon, it is likely that the lithium ion is coordinated to oxygen during the rearrangement. 

Poor to modest yields of trinitromethyl compounds are reported for the reaction of silver nitroform with substituted benzyl iodide and bromide substrates. Compounds like (36), (37), and (38) have been synthesized via this route these compounds have much more favourable oxygen balances than TNT and are probably powerful explosives." The authors noted that considerable amounts of unstable red oils accompanied these products. The latter are attributed to O-alkylation, a side-reaction favoured by an SnI transition state and typical of reactions involving benzylic substrates and silver salts. Further research showed that while silver nitroform favours 0-alkylation, the sodium, potassium and lithium salts favour C-alkylation." The synthesis and chemistry of 1,1,1-trinitromethyl compounds has been extensively reviewed. The alkylation of nitronate salts has been the subject of an excellent review by Nielsen." ... 

A triply chelating ligand is the purpurate anion, (/), the ammonium salt of which is the indicator murexide. The kinetics of its complex formation with alkali metals have been reviewed (75). In the lithium salt the cation is 5-coordinated in a square pyramid with the base formed by the three donor atoms, 0, N, O from one anion and a carbonyl oxygen from... 

The reaction mechanism for A-oxidation by performic acid has been studied by AMI calculation methods.174 The iminium salt A-mcthyl-3,4-dihydroisoquinolinium p-toluenesulfonate has been used to catalyse the oxidation of the azo dye calmagite by peracetic acid. The mechanism at pH 10 involves peracid oxidation of the quinolinium ion to form an oxaziridinium salt, which then acts as an oxygen transfer agent for oxidation of cahnagite.175 The presence of lithium salts affects the course of the reaction determining the formation of benzoyl peroxide and benzoic acid as final products in the oxidation of benzaldehyde by perbenzoic acid.176,177... 

The next part of the present study concerns the oxidation of the phosphonate and thiophosphonate carbanions. Generally, this reaction was found to occur in two directions depending on the structure of the starting phosphonate and the reaction conditions. The lithium salts of thiophosphonate carbanions 5 give on treatment with oxygen the corresponding a-hydroxy thiophosphonates exclusi vely. 

As expected, the reaction of the lithium salts of phosphonates with oxygen results in the formation of dialkyl phosphoric acids-8 and carbonyl products i.e. the cleavage of the C-P bond takes place (, 5). However, when the halomagnesiurn salts of phosphonates Z were oxidized, a-hydroxyphosphonates 2 were formed. 

Other conceivable routes to 42, for instance the oxidation of the lithium salt of a-lithiocyclopropanecarboxylic acid 97) with molecular oxygen 98), have failed 39). 

Typical examples of the first group are polyethylene oxide [140-144] and polypropylene oxide [145-146] mixed with lithium salts. The oxygen atoms of these polymers interact with the Li ions and solvate them, and thus the Li salt may be uniformly dissolved in these polymers. 

In the reaction of the lithium salt of 62 with acetone after a short lithiation time of 30 min, a 10% or 25% E Z mixture of 63 was obtained together with the addition product 64 in 65% yield (equation 42)65. The formation of only one addition product, and the quick disappearance of the -isomer, are due to a fast deprotonation process the -isomer compared with the Z-isomer, and the high rate of equilibration between the lithium compounds that greatly favors the syn anion, which reacts with acetone to give 64. These results point out that the formation of the syn lithium compounds is favored in oxime ethers for kinetic as well as for thermodynamic reasons. The kinetic preference, according to Ensley and Lohr65, is due to coordination between the lithium amide and the oxime oxygen. 

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