Question

IUPAC name of the \[{\text{C}}{{\text{H}}_3} - {\text{O}} - {{\text{C}}_2}{{\text{H}}_5}\] is:
(A) Ethoxymethane
(B) Methoxyethane
(C) Methylethyl ether
(D) Ethylmethyl ether

Answer 1

Hint: While naming an organic compound by IUPAC rules, we first find out the longest continuous chain of C atoms i.e. parent chain.Ether group is a class of organic compounds in which an oxygen atom is connected to two alkyl or aryl groups. The bonding of oxygen in water, alcohol and ethers is nearly similar.

Complete step by step answer: First we will find out the parent chain and the number of C atoms in it. Here, the longest chain is 2C i.e. ethane.
The functional group is . Hence, it is an ether.
According to IUPAC conventions, the name of \[{\text{R - O - R}}\] type of ether is written as alkoxy alkane.
Lower member of the alkyl group is written as alkoxy and the higher member is written as alkane.

So, the IUPAC name of \[{\text{C}}{{\text{H}}_3} - {\text{O}} - {{\text{C}}_2}{{\text{H}}_5}\] is Methoxy ethane i.e. option B.

Additional information: IUPAC is a systematic approach for nomenclature of organic compounds as per the rules set by International Union of Pure and Applied Chemistry.
While naming compounds in IUPAC system, all the compounds containing C as the principal element are considered as ‘organic compounds’. Other elements such as O, H and N which are usually associated with C are considered as functional groups.
Ethers are the compounds having an oxygen atom attached to two same or different alkyl groups. Based on the type of substituent attached ethers are classified into two broad groups-
Symmetrical ethers – The two alkyl groups attached are the same.
Asymmetrical ethers – The two alkyl groups attached are different.
Here, \[{\text{C}}{{\text{H}}_3} - {\text{O}} - {{\text{C}}_2}{{\text{H}}_5}\] is an example of asymmetrical ether.
Ethers are colourless, sweet smelling compounds. They are most commonly used as disinfectants and refrigerants.

Note: While counting the C chain, be careful to find the longest one. The name of the longest chain comes in ‘alkane’ and the name of the shorter chain comes in ‘alkoxy’.