Subject - Organic Chemistry

In a narrow sense, esters are organic compounds of the formula R-CO-O-R' with R'≠H. Ethylacetate, ${\text{H}}_3\text{C}-\text{C}\text{O}-\text{O}-{\text{C}}_2{\text{H}}_5$, frequently used as solvent, is an important representative of this compound class. Esters can be prepared from carboxylic acids and alcohols or phenols with loss of water.

R-COOH + R'-OH → R-CO-O-R' + ${\text{H}}_2\text{O}$

The use of proton acids other than carboxylic acids in the synthetic scheme mentioned above leads to an extended class of esters. Examples are methyl nitrate ${\text{H}}_3\text{C}-\text{O}-\text{N}{\text{O}}_2$, an ester of nitric acid, and dimethyl sulfate ${\left({\text{H}}_3\text{C}\right)}_2\text{S}{\text{O}}_4$, an ester of sulfuric acid.