Question

What are ethers? How are they classified?

Answer 1

Organic compounds which contain an oxygen atom which is connected to two alkyl or aryl groups are together called ethers. And it has a general formula $R - O - {R'}$ , where $R$ and ${R'}$ represent the alkyl or aryl groups.

Complete step by step answer: Firstly, Ethers can be defined as the organic compounds which consists of an oxygen atom which is connected to two alkyl groups or aryl groups, some of the examples of ethers are diethyl ether $(\;C{H_3}C{H_2}OC{H_2}C{H_3})$ or ethylene glycol dimethyl ether $(\;C{H_3}OC{H_2}C{H_2}OC{H_3})$ etc. And it has a general formula of $R - O - {R'}$ , where $R$ and ${R'}$ represent the alkyl or aryl groups. Ethers have linkage which has a bond angle of about ${110^o}$ and $C - O$ distance of about $140$ pm (picometer). The bonding of oxygen in ethers, alcohols, and water is considered to be the same as the hybridization at oxygen is $s{p^3}$ . Ethers are common in organic chemistry but are more relevant in biochemistry, as these linkages are common linkages in carbohydrates and many other biochemical compounds.
Further, Ethers can be classified into two categories:

a) Symmetrical ethers: If the alkyl or aryl groups are the same on both sides of the oxygen atom, then it is known as a simple or symmetrical ether. Its examples are:- diethyl ether $(\;C{H_3}C{H_2}OC{H_2}C{H_3})$ , dipropyl ether $(C{H_3}C{H_2}C{H_2}OC{H_2}C{H_2}C{H_3})$ etc.

b) Unsymmetrical ethers: If the alkyl or aryl groups are different on the sides of the oxygen atom, the ethers are known as mixed or unsymmetrical ethers. Its examples are:- ethyl methyl ether $(C{H_3}OC{H_2}C{H_3})$ , methyl phenyl ether $(C{H_3}O{C_6}{H_5})$ .

Note: The nomenclature of the compounds mentioned above is not the IUPAC nomenclature. Ethers are classified as symmetrical ethers and asymmetrical ethers.