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-

he next several chapters deal with the chemistry of various oxygen-containing functional groups. The interplay of these important classes of compounds-alco- hols, ethers, aldehydes, ketones, carboxylic acids, and derivatives of carboxylic acids-is fundamental to organic chemistry and biochemistry

n contrast to alcohols with their rich chemical reactivity, ethers (compounds contain- ing a C-0-C unit) undergo relatively few chemical reactions. As you saw wher we discussed Grignard reagents in Chapter 14 and lithium aluminum hydride reduc- tions in Chapter 15, this lack of reactivity of ethers makes them valuable as solvents in a number of synthetically important transformatio. In the present chapter you will learn

ADDITION TO THE CARBONYL GROUP Idehydes and ketones contain an acyl group RC-bonded either to hydrogen or to another carbon

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

arboxylic acids, compounds of the type RCOH, constitute one of the most fre- quently encountered classes of organic compounds Countless natural products are carboxylic acids or are derived from them. Some carboxylic acids, such as acetic acid, have been known for centuries. Others, such as the prostaglandins, which are pow erful regulators of numerous biological processes remained unknown until relatively

ACYL SUBSTITUTION his chapter differs from preceding ones in that it deals with several related classes of compounds rather than just one. Included are 1. Acyl chlorides, RCCI 2. Carboxylic acid anhydrides, RCOCR 3. Esters of carboxylic acids, RCOR'99

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

itrogen-containing compounds are essential to life. Their ultimate source is atmo- spheric nitrogen which, by a process known as nitroge. nitrogen fixation, is reduce ced to ammonia, then converted to organic nitrogen compounds. This chapter describes the chemistry of amines, organic derivatives of ammonia. Alkylamines have their nitro- gen attached to sp'-hybridized carbon; arylamines have their nitrogen attached to an sp2-hybridized carbon of a benzene or benzene-like ring

he value of alkyl halides as starting materials for the preparation of variety of organic functional groups has been stressed many times. In our earlier discussions, we noted that aryl halides are normally much less reactive than alkyl halides in reactions that involve carbon-halogen bond cleavage. In the present chapter you will see that aryl halides can exhibit their own patterns of chemical reactivity, and that these reac