ou have already had considerable experience with carbanionic compounds and rgani their applications in synthetic organic chemistry. The first was acetylide ion in Chapter 9, followed in Chapter 14 by organometallic compounds-Grignard reagents, for example-that act as sources of negatively polarized carbon. In Chapter 18 you learned that enolate ions-reactive
the preceding chapter you learned that nucleophilic addition to the carbonyl group is one of the fundamental reaction types of organic chemistry. In addition to its own reactivity, a carbonyl group can affect the chemical properties of aldehydes and ketones in other ways. Aldehydes and ketones are in equilibrium with their enol isomers
rganometallic compounds are compounds that have a carbon-metal bond; they lie at the place where organic and inorganic chemistry meet. You are already familiar with at least one organometallic compound, sodium acetylide (NaC=CH), which has an ionic bond between carbon and sodium. But just because a compound contains both a metal and carbon isn't enough to classify it as organometal-
