Αποτελέσματα Αναζήτησης
Anhydrides react rapidly with water to form two carboxylic acids compounds. Because anhydrides are often prepared from carboxylic acids this reaction serves little synthetic value.
This page looks at the reactions of acid anhydrides with water, alcohols and phenols (including the manufacture of aspirin). These reactions are all considered together because their chemistry is so similar. There is also a great similarity between acid anhydrides and acyl chlorides (acid chlorides) as far as these reactions are concerned.
23 Ιαν 2023 · This page looks at the reactions of acid anhydrides with water, alcohols and phenols (including the manufacture of aspirin). These reactions are all considered together because their chemistry is so similar.
Acid chlorides react with carboxylic acids to form anhydrides as shown in the reaction below. Some cyclic anhydrides can be synthesized from the corresponding dicarboxylic acid with gentle heating. The example below shows the reaction of glutaric acid to form a cyclic anhydride.
Acid anhydrides are made from two carboxylic acid groups joined together. To form an acid anhydride, a water molecule is lost in a condensation reaction between two carboxylic acids. This is why acid anhydrides are called anhydride – lack of water.
Acid anhydrides (sometimes simply called "anhydrides", but this is less specific) are compounds formed by dehydration of two acidic groups. They form the basis for the synthesis of imides or can be used to create esters (with alcohols), amides (with amines) or alcohols (via reduction).
Reactions of Acid Anhydrides The chemistry of acid anhydrides is similar to that of acid chlorides, although anhydrides react more slowly. Thus, acid anhydrides react with water to form acids, with alcohols to form esters, with amines to form amides, and with LiAlH 4 to form primary alcohols.
