CH2CH3

CH2CH3 is a shorthand notation commonly used to denote the ethyl group, a two-carbon alkyl substituent with the formula C2H5. In structural notation, the fragment is often written as CH3-CH2-, with the point of attachment at the CH2 carbon (ethan-1-yl). The ethyl group is one of the simplest and most widely encountered alkyl substituents in organic chemistry; its common abbreviation is Et.

As a substituent, CH2CH3 appears in a broad range of compounds. It is derived from ethane by removing one hydrogen, and it appears in many everyday chemicals and industrial materials. Examples include ethanol (CH3CH2OH), ethyl chloride (C2H5Cl), ethyl acetate (CH3COOCH2CH3), and diethyl ether (CH3CH2OCH2CH3). In chemical reactions, the ethyl moiety can be transferred or introduced via ethylation processes, and it features as a constituent in various esters, ethers, and amines.

Reactivity and transformations involving the ethyl group include oxidation of ethanol to acetaldehyde and then to acetic acid, as well as various substitution and addition reactions where the CH2CH3 fragment is retained or relocated within larger molecules. The CH2CH3 fragment therefore plays a central role in forming and modifying a wide array of organic compounds.

See also: Ethyl, Ethane, Ethene, Ethanol.