Organic Chemistry

In Chapter 8, you will learn about the reactions of

dienes—hydrocarbons that have two carbon–carbon

double bonds. You will see that if the two double bonds in

a diene are sufficiently separated, most reactions that

occur are identical to those of alkenes (Chapter 4). If,

however, the double bonds are separated by only one sin-

gle bond, electron delocalization (Chapter 7) plays an im-

portant role in the reactions of the compound. Notice how

this chapter combines many of the concepts and theories

introduced in previous chapters.

Chapter 9covers the reactions of alkanes—hydrocarbons

that contain only single bonds. In the previous chapters,

you saw that when an organic compound reacts, the

weakest bond in the molecule is the one that breaks first.

Alkanes, however, have only strong bonds. Knowing this,

you can correctly predict that alkanes undergo reactions

only under extreme conditions.

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