The range of alkoxy groups is vast, the simplest being methoxy (CH3O−).
[1] An ethoxy group (CH3CH2O−) is found in the organic compound ethyl phenyl ether (C6H5OCH2CH3, also known as ethoxybenzene).
An alkoxy or aryloxy group bonded to an alkyl or aryl (R−O−R') is an ether.
The term alkoxide refers to the anionic conjugate bases of alcohols (RO−) or to ionic compounds containing such an anion.
Alkoxide compounds are derivatives of alcohols where the hydrogen of the –OH group is replaced by a metal;[2] for example, the sodium salt of ethanol (CH3CH2OH) is sodium ethoxide, containing ethoxide anions CH3CH2O− and sodium cations Na+.