Reactivity ionic

Much effort has gone into detenuining these quantities since they are fundamental to ionic reactivity. Examples include thenuodynamic equilibrium measurements for all quantities and photoelectron studies for detenuination of EAs and IPs. The most up-to-date tabulation on ion thenuochemistry is the NIST Chemistry WebBook (webbook.nist.gov/chemistry) [123]. 

For ionic reactivity two cases must be considered depending on the electron demand the thiazole ring may either be electron donating or electron accepting. 

Additional examples of the ionic reactivity of germanium and tin systems in the gas phase deserve particular attention. For example, tritiated methyl cations have been used... 

Since reactions in a mass spectrometer are generally less selective than their thermal or photochemical analogs, and since more energy is generally available to reactions of a molecule ion, it is inevitable that some reactions will be more or less unique to mass spectrometry. Whenever this occurs the correlation of ionic reactivity with the reactivity of neutrals will be incomplete. 

The pericyclic ring opening of halocyclopropanes that occurs on solvolysis was directly paralleled by the gas phase ionic reactivity of the same compounds. ) The ring opening of 42 was the most facile in a series (Eq. (28)). The same compound eliminated bromide from the molecule ion much more readily than related isomers. Evidently it makes little difference to the reactivity if the leaving group is Br— or Br . 

Kajdas, C. (1994) Importance of ionic reactive intermediates for lubricant component reactions with friction surfaces. iMbr. Sci. 6 203-228. 

Where they are known, the organic compounds of Ca, Sr and Ba are highly ionic, reactive, and of little utility or importance. Magnesium compounds, of which the Grignard reagents are the best known, are probably the most widely used of all organometallic compounds. They are employed for the synthesis of alkyl and aryl compounds of other elements as well as for a host of organic syntheses. 

Overall ionic reactivity is also lower in cyclopropane than in propene [29, 175, 269, 285]. Total reaction rate coefficients and rate coefficients for some of the major reactions of the parent ions of propene and cyclopropane are given in Table 8. The lower reactivity in cyclopropane also seems to be pertinent to higher-order reactions. Thus, while poly-... 

Kropp and coworkers have been concerned with systems in which homolysis is followed by rapid electron transfer, such as the photolysis of certain alkyl halides [55]. Photolysis of the norbomyl phenyl sulfoxide 110 was examined. The notion was that sulfide photolysis is usually homolytic, but the sulfinyl radical is more electronegative than the sulfenyl (thiyl) radical, which might assist in electron transfer reactions. Thus, it was thought, ionic reactivity might be observed. In addition to inversion of the sulfur center and deoxygenation (yide infra), norbomane 111 and norbomene 112, both presumed to... 

Because radical brominations are so selective, they can be used successfully in the laboratory to make alkyl bromides. There are relatively few ways of functionalizing an unfunctionalized centre, and radical allylic bromination is one of the most effective. We introduced this reaction in Chapter 24, where we contrasted the radical reactivity of Bt2 towards alkenes (leading to an allyl bromide by hydrogen abstraction) with its ionic reactivity (leading to addition of bromine across the alkene). We can now look in a little more detail at the selectivities involved. 

A number of theoretical studies of varying degrees of sophistication have appeared on fluoroethylenes, but they have yet to attain the accuracy of precise experimental studies. They include the following ab initio calculations on tetra-fluoroethylene, mono-, di-, - and tri-fluoroethylenes, extended Hiickel MO calculations on fluorinated ethylenes and buta-l,3-dienes, semi-empirical calculations on ionic reactivities of fluoro-olefins,i CNDO- and INDO-type calculations on fluoroethylenes, 1,1-dichlorodifluoro- and chlorotrifluoro-ethylene, hexafluoropropene and octafluoroisobutene, on the polymerization of vinyl fluoride,... 

In this chapter, we will first describe and evaluate the various experimental methods which have been used to obtain information about the structures of hydrocarbon ions. We will then review the information currently available on the structures of these ions formed in various systems. Finally, we will examine the rates of some of the reactions of various isomeric ions for information about the effect of structure on ionic reactivity. 

Lehn, J. M., Cryptate inclusion complexes Effects on solute-solute and solute-sol-vent interactions and on ionic reactivity. Pure Appl. Chem., 52, 2303, 1980. 

Photolysis of aryl azides in acidic media represents a special case. At low pH, singlet aryl nitrenes may be N-protonated, rapidly yielding singlet nitrenium ions. These ionic reactive intermediates undergo reactions different from those of singlet nitrenes. 

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