ester..

An ester is an organic compound which has an alkyl group on both sides of -COO- like

-COO- will be their in all esters with two alkyl groups on either sides.

R and R' may be same or different.

Alkyl groups may be CH₃ - which is methyl,

C₂H₅ - which is ethyl.

C₃H₇ - which is propyl

WHile naming an ester, R' alkyl group is named first as explaiend above.

Then count the carbons present in R group add one carbon for the COO group and then write it as alkanoate.

 

Example:

C₂H₅COOCH₃ is named as

 

Similarly instead of craming you can name the compound logically. It will be easy. If still there is some difficulty put another query.