Introduction, nomenclature, classification, isomerism in ether

Nomenclature of ethers
Common names of ethers follow after the names of alkyl / aryl groups written as separate words in alphabetical order. The word ether is added at the end.

In case of simple ethers, the prefix di is attached before the name of the alkyl group.

Examples:

C2H5 - O - C2H5 is Diethyl ether

C6H5 - O - C6H5 is Diphenyl ether

C2H5 - O - C6H5 is Dthyl phenyl ether.

According to the IUPAC nomenclature ethers are regarded as hydrocarbon derivatives in which a hydrogen atom is replaced by an alkoxy group - OR, the larger group (R) being chosen as the parent hydrocarbon. Ethers are named as alkoxyalkenes. The larger alkyl group forms the part of parent chain while lower alkyl group constitutes the alkoxy radical.

Examples:

methoxyethane

The numbering of the parent chain is done so that the carbon atom linked to the -O-atom gets the lowest number.

Classification of ether

Ethers are known as simple or symmetrical, if the two alkyl or aryl groups attached to the oxygen atom are same.

Example: C2H5 - O - C2H5 is called diethyl ether and is a simple ether.

Ethers are known as mixed or unsymmetrical if the two groups attached to the oxygen atom are different.

Example: C2H5 - O - CH3 called ethyl methyl ether is a mixed ether.

Isomerism in ether

Aliphatic Ethers can give two different types of isomers.

1. Chain isomerism

Ethers with the same formula and having different carbon chain skeletons are called chain isomers.

Examples:

chain isomers of ethers

2. Functional isomers

Ethers are isomeric with alcohols.

Example:

Ethers are isomeric with alcohols

is isomeric with ethyl alcohol C2H5OH.

3. Metamerism

Isomers with the same molecular formula but different alkyl groups (around the functional group) are called metamers. An ether with formula C4H10O has 3 metamers.

metamerism in ethers

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