Aldehydes and ketones are obtained as products from many reactions discussed in previous sections of this text. The following diagram summarizes the most important of these. To review the previous discussion of any of these reaction classes simply click on the number (1 to 5) or descriptive heading for the group.
With the exception of Friedel-Crafts acylation, these methods do not increase the size or complexity of molecules. In the following sections of this chapter we shall find that one of the most useful characteristics of aldehydes and ketones is their reactivity toward carbon nucleophiles, and the resulting elaboration of molecular structure that results. In short, aldehydes and ketones are important intermediates for the assembly or synthesis of complex organic molecules.