The group of chemical compounds which are formed by bonding of an alcohol group with a group of organic acids, by losing water molecules is called as Esters. Esters are polar in nature but not more than alcohols.
- These chemical compounds participate in the formation of hydrogen bonds as the acceptors of hydrogen-bond, but they cannot act as the hydrogen-bond donors.
- This ability to participate in the hydrogen bonding benefits some water-solubility.
General formula of esters
The formula for carboxylic acid esters is RCOOR’ (where R and R’ are any organic combining groups). Esters feature a carbon-to-oxygen double bond that is also singly bonded to a second oxygen atom. The oxygen atom is further connected to an aryl or an alkyl group. They come in all shapes and sizes.
Formation of ester
Esters are formed when the carboxylic acid is heated with the alcohol in the presence of a catalyst.
- In this reaction, the concentrated sulphuric acid is used as a catalyst, dry form of hydrogen chloride gas is used in some cases.
- This method of reaction is used to convert alcohols into an ester.
- This reaction does not work for the compounds containing the OH- Group directly attached to the benzene ring.
This method of reaction is called Esterification Reaction. Methyl butanoate is an example of ester.