This is the diagram for an ether. “R” represents the rest of the compound. Both R's do not have to be identical.
Ethers are organic compounds that contain an ether functional group. This functional group is defined by the general formula of R-O-R’, where the oxygen atom is bounded to two carbon atoms.
Although ethers contain the electronegative element oxygen, ether molecules as a whole are either negligibly polar or nonpolar. The oxygen-carbon bond in ether is still polar due to the large electronegativity difference between the two elements, but the relative symmetry of the R-O-R’ bonds causes the ether molecule as a whole to be only slightly polar. Under most circumstances, ethers can be considered to be nonpolar. Generally, ethers share similar qualities with alkanes, or single-bonded hydrocarbons without any cyclic structures.
A physical property of ethers is a relatively low boiling point in comparison to the boiling point of alcohols. Unlike alcohols, ethers do not form hydrogen bonds. This is because the oxygen’s two valence electrons are bounded to carbons instead of hydrogens. Ethers only experience van der Waals forces, also known as London dispersion forces. These are the weakest intermolecular forces, much weaker than hydrogen bonds and dipole-dipole interactions (see the chapter Background - Things you should know for more details). It does not take large amounts of energy in the form of heat to tear apart the bonds between ether molecules. Therefore, ethers boil at a relatively low temperature.
Naming simple ethers requires you to think of the ether molecule as two carbon chains separated by an oxygen. Two alkyl groups surround the oxygen, one on each side. To name the ether molecule, first determine the names of those two alkyl groups. Then list the two alkyl groups in alphabetical order before the word ether so that the name of the ether is in the form of “alkyl alkyl ether.” If the two alkyls are the same, you will put “dialkyl ether,” with the appropriate alkyl being substituted in for “alkyl.”
This molecule is ethyl methyl ether.
An example of this would be CH3CH2OCH3. The oxygen separates an ethyl group (CH3CH2) from a methyl group (CH3). Therefore, the name of this molecule would be ethyl methyl ether.
This naming scheme only works for simple ethers. Complex ethers require different steps to be named. For more information about naming complex ethers, visit: