Nucleophilic substitution reactions carboxylic acid derivatives

Acid chlorides can be converted to acid anhydrides, esters, or amides. These reactions are possible because acid chlorides are the most reactive of the four carboxylic acid derivatives. Nucleophilic substitutions of the other acid derivatives are more limited because they are less reactive. For example, acid anhydrides can be used to synthesise esters and amides, but cannot be used to synthesise acid chlorides. 

Carboxylic acid derivatives undergo substitution reactions with nucleophiles, such as water, organometaUic compounds, and hydride reducing agents. These transformations proceed through the familiar (often acid- or base-catalyzed) addition-elimination sequence (Section 19-7). 

Carboxylic Acid Derivatives Nucleophilic Acyl Substitution Reactions... 

Carboxylic acid and its derivatives undergo nucleophilic acyl substitution, where one nucleophile replaces another on the acyl carbon. Nucleophilic acyl substitution can interconvert all carboxylic acid derivatives, and the reaction mechanism varies depending on acidic or basic conditions. Nucleophiles can either be negatively charged anion (Nu ) or neutral (Nu ) molecules. 

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