ethan1yl

Ethan1yl is the systematic name for the ethyl radical, also known as the ethan-1-yl substituent. It is a monovalent alkyl radical derived from ethane by the removal of one hydrogen atom. In chemical notation, it is represented as C2H5• (or CH3-CH2•). The ethyl radical is highly reactive and exists primarily as an intermediate in chemical transformations rather than as a freely isolable species under ordinary conditions.

Structure and symmetry: The radical is attached through the first carbon of the ethane skeleton; because ethane is symmetric, removing a hydrogen from either carbon yields the same ethan-1-yl radical. This equivalence underpins the conventional naming that may also be encountered as ethan-2-yl in some historical texts, though ethan-1-yl is the standard IUPAC designation today. The common substituent name for this radical is ethyl.

Reactivity and role: Ethan-1-yl participates in a wide range of organic reactions as a reactive intermediate. It can engage in radical additions to alkenes, hydrogen abstraction, and cross-coupling processes that form new carbon–carbon bonds. In many reaction mechanisms, the ethyl radical is generated in situ from other precursors (such as photochemical or thermal activation) and rapidly combines with substrates to give ethyl-containing products. Because it is transient, precise handling relies on generating it in the reaction mixture rather than isolating it.