Carbocations destabilisation

Inductive electron withdrawal ( l[Pg.15]

Later discussion will show that fluorine directly attached to a carbocation centre, as in 1.16A and 1.17 A, overall is clearly a stabilising influence, but the effect of fluorine more remote from the centre, as in 1.16B, is strongly destabilising. 

The orientations of addition (Table 7.8) are consistent with an electrophilic process (Figure 7.50), bearing in mind that fluorine attached to positively charged carbon, C+ —F, is stabilising whereas fluorine that is (S- to the carbocation centre is destabilising (Chapter 4, Section VI). 

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