Carbocations structure and

There are at least two other studies of competitive reactions to form the products of solvolysis and elimination reactions that may provide insight into the relationships between carbocation structure and reactivity toward nucleophile addition and deprotonation. 

In a search fora pure y-deuterium equilibrium isotope effect, Kates (1978) studied [67] using C-nmr spectroscopy. The results showed equilibrating carbocation structures, and from the isotopic splitting of shifts of methyl groups equilibrium constants were determined. 

An understanding of carbocation structure and relative stability is important for learning a variety of reaction processes. 

Throughout the discussion of carbocation structure and reactivity, we have encountered examples of bridged species that require expansion of bonding concepts... 

Whenever a carbocation is an intermediate in a mechanism, rearrangements are possible. Besides the study of carbocation structures and reactivity in stable ion media, the majority of the information chemists have on carbocation rearrangements comes from SnI solvolysis reactions. A hydrogen, alkyl, or aryl group on a carbon adjacent (p) to the cationic carbon can shift to form a different carbocation. This is called a Wagner-Meerwein shift. Eq. 11.30 shows a thermoneutral example. 

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