ABSTRACT
Aldehydes and ketones are produced by the oxidation of primary or secondary alcohols, respectively, and are defined by the presence of a carbonyl (C=O) functional group. Aldehydes and ketones are substantially more polar than alcohols, but they cannot hydrogen bond and so typically have lower boiling points than the corresponding alcohol. Aldehydes and ketones react through the addition of the highly electrophilic carbonyl carbon atom. In this chapter, we will consider oxygen, nitrogen, and carbon nucleophiles and their mechanism for addition reactions with aldehydes and ketones. Aldehyde and ketones are also weak acids at the α carbon (the carbon next to the carbonyl carbon). The reactivity at the α carbon will be considered in detail in a later chapter, but this chemistry will be introduced and briefly considered in this chapter. Finally, aldehydes can be further oxidized to carboxylic acids and both aldehydes and ketones can be reduced (to alcohols and alkanes) with hydrogenation or with hydride reagents. Completion of this chapter substantially increases the synthetic tools available to students of organic chemistry.
