Synthesis ionic compounds

Ionic liquid synthesis in a commercial context is in many respects quite different from academic ionic liquid preparation. While, in the commercial scenario, labor-intensive steps add significantly to the price of the product (which, next to quality, is another important criterion for the customer), they can easily be justified in academia to obtain a purer material. In a commercial environment, the desire for absolute quality of the product and the need for a reasonable price have to be reconciled. This is not new, of course. If one looks into the very similar business of phase-transfer catalysts or other ionic modifiers (such as commercially available ammonium salts), one rarely finds absolutely pure materials. Sometimes the active ionic compound is only present in about 85 % purity. However, and this is a crucial point, the product is well specified, the nature of the impurities is known, and the quality of the material is absolutely reproducible from batch to batch. 

Solomon, Kinetics of Synthesis and Decomposition Reactions of Ionic Compounds Containing N-F Cations , Illinois Institute of Technology Research Institute, IITRI C-6140 (Jan 1969), AD-682497, p 5 CA 77, 131206 (1972)... 

C04-0120. Devise a synthesis, write the net ionic reaction, and compute masses of each starting material needed to make 2.50 kg of each of the following solid ionic compounds (a) FePOq (b) Zn (OH)2 (c)... 

The conversion of alcohols directly into the structurally related hydrocarbons by ionic hydrogenation can provide a means of synthesis for compounds that would be extremely difficult or impossible to obtain by other methods. A good example is the synthesis of 2-terr-butyladamantane (12, R = Me). This interesting, highly strained compound may be synthesized in moderate overall yield by a conventional multiple-step route.149 Alternatively, it is obtained in 90% isolated yield upon treatment of a dichloromethane solution of the readily available 2-/c/7-bulyI -2-adamantanoI (11, R = Me)150 and one equivalent of either tri-n-hexylsilane151152 or triethylsilane153 with trifluoroacetic acid at room temperature (Eq. 16). 

The synthesis of non-ionic contrast agents is much more complicated. Due to the higher aqueous solubility of the intermediates, purification processes have to be more sophisticated than for the ionic compounds. Moreover, for the carboxylic acid, salt purification procedures of ionic substances are no longer available for the non-ionic derivatives. Now, recrystallisation. 

Two general methods have been described for the synthesis of this new class of meso-ionic compounds (196). The most convenient method is by the treatment of 4-bromo-l,2,3-triazolium salts (197, X = Br) with sodium sulfide in dimethylformamide. Alternatively, N-methylation of the isomeric 4- or 5-alkylmercapto-1,2,3-triazoles 198 or 199 with methyl tosylate gave intermediate triazolium salts (197, X = SR, Y = Tos), which yielded meso-ionic l,2,3-triazole-4-thiones (196) by 5-dealkylation by heating with piperidine. 

A number of general methods for the synthesis of meso-ionic 1,2,4-triazol-3-ones are available. Sodium ethoxide-catalyzed cyclization of 1-benzoyl-l,4-diphenylsemicarbazide (201, R = R = R = Ph, X = O) yielded anhydro-3-hydroxy-1,4,5-triphenyl-1,2,4-triazolium hydroxide (200, R = R = R = Ph). A general route to meso-ionic 1,2,4-triazol-3-ones (200) is exemplified by the formation of the 1,4,5-triphenyl derivative (200, R = R = R = Ph) from A-amino-MA -diphenylbenzamidine (202, R = R = R = Ph) and phosgene. In contrast with this ready meso-ionic compound formation, the corresponding reaction of the iV-methylbenzamidine (202, R = Me, R = R = Ph) did not yield the meso-ionic 1,2,4-triazol-3-one (200, R = Me, R = R = Ph). The product was in fact 3,4-diphenyl-2-methyl-l,2,4-triazol-5-onium chloride (203), which on heating gave 3,4-diphenyl-1,2,4-triazol-5-one (204, R = Ph). The formation of the A-methyl derivative (200, R = Me, R = R = Ph, yield 79%) by heating the 7V-thiobenzoyl semicarbazide (201, R = Me, R = R = Ph, X = S) with potassium carbonate in methyl cyanide has been reported. Another synthesis of A-methyl derivatives (200, R = Me) involves methylation of 3-methyl-4-phenyl-l,2,4-triazol-5-one (204,... 

When Busch s endo-thiotriazolines were formulated as meso-ionic compounds, it was recognized that two constitutional possibilities (227 or 228) required consideration. Later studies - established that the endo-thiotriazolines were in fact the meso-ionic l,2,4-triazole-3-thiones (227). Recently, a specific synthesis of their meso-ionic isomers (228) has been reported, and under equilibration conditions in hot ethanol the rearrangement 228 - 227 occurs. This explains why the meso-ionic l,2,4-triazole-3-thiones (227) are the products of synthetic... 

These heterocycles (240) are the first representatives of meso-ionic compounds to be S3mthesized in which the raocyclic subsfituent f. Table I) is a stabilized carbanionoid group [-C(CN)C02Me or -CfChOi]-Their synthesis d involves the reaction between (i) JV-aminoamidines (23 ) and bis(methylthio)acrylonitriles (241), (ii) iV-thioacylhydrazines (232), and 3-alkylamino-3-methylthioacrylonitriles (242), and (iii) 1,2,4-triazolium iodides (234, R = Me, X = I) and malononitrile. 

The synthesis of NAT was performed by reaction of the methylester of PCA with the acetonide of l,3,4-trihydroxybut-2-yl amine. After saponification with diluted sulfuric acid the neutral (non-ionic) compound NAT has been obtained [48]. 

The above characterizations primarily concern the interactions between molecular solutes and ILs. However, ILs are also good solvents for ionic compounds, and have been studied extensively as media for transition metal catalysis [4, 38, 219] and for the extraction of heavy metals [23]. ILs are capable of solvating even simple salts, such as NaCl, to some degree [219], and in fact the removal of halide impurities resulting from synthesis can be a considerable challenge [68]. However, ionic complexes are generally far more soluble than simple salts [220], and we focus our attention on these systems as they have received greater study and are more relevant to the processes noted above. 

These compounds may be prepared by direct reaction between Li metal and alkyl halides and are useful reagents for preparing organometallic compounds of other elements, and as alternatives to Grignard reagents in organic synthesis. Organometallic compounds of the other elements form solids with somewhat more ionic character. 

If the reactants in an equation are two elements, the only way in which they can react is to form a binary compound, which is composed of two elements. Often, when a metal reacts with a nonmetal, electrons are transferred and an ionic compound is formed. You can use the charges of the ions to predict the formula of the compound formed. Metals in Groups I and 2 lose one electron and two electrons, respectively. Nonmetals in Groups 16 and 17 gain two electrons and one electron, respectively. Using the charges on the ions, you can predict the formula of the product of a synthesis reaction, such as the one in Figure 10. 

One of the defining characteristics of single-replacement and combustion reactions is that they always involve the transfer of electrons from one atom to another. So do many, but not all, synthesis and decomposition reactions. For example, you studied the synthesis reaction in which sodium and chlorine react to form the ionic compound sodium chloride. 

The synthesis of nonionic bis compoundsis analogous to that of ionic compounds, except... 

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