The ether functional group is characterized by the presence of an oxygen atom shared by two carbons (can be alkyl or aryl groups). It is therefore a functional group that appears in an internal position within the molecules. Its general formula is C1-O-C2.
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The C-O-C bond angle has about 104.5 °, with a bonding distance of 140pm. The ether group is a polar functional group, because the COC bond angle is not 180°, which impairs the molecule dipoles to cancel each other. Although it cannot function as an H donor in hydrogen bonds, it can function as an acceptor of them.
In biochemistry, the ether groups are present, for example, in the O-glycosidic bonds.