Substitution reactions aliphatic nucleophilic: examples illustrating

Nucleophilic substitution reactions, and others involving attack by nucleophilic species on fully and partially saturated systems, form a very heterogeneous set of reactions, from which we select only a few representative examples to illustrate special points. For the most part, the reactions involved are of the kind familiar from aliphatic chemistry. 

The familiar substitution reactions of derivatives of carboxylic acids with basic reagents illustrate nucleophihc substitution at aliphatic sp carbons. (Substitution reactions of carboxylic acids, and their derivatives, with acidic reagents are covered in Chapter 4.) The mechanisms of these reactions involve two steps (1) addition of the nucleophile to the carbonyl group and (2) elimination of some other group attached to that carbon. Common examples include the basic hydrolysis and aminolysis of acid chlorides, anhydrides, esters, and amides. 

Nucleophilic substitution at aliphatic carbon is a reaction that plays an important role in organic synthesis. The use of the reaction in construction of carbon-carbon bonds will be discussed in Part B, but the role of the reaction in interconverting certain functional groups has such a basic place in organic chemistry that it is appropriate to illustrate some examples of the synthetic utility of nucleophilic substitution. The conversion of alcohols to alkyl halides and the conversion of alcohols to ethers are among the most fundamental organic transformations. 

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