2ethylhexan1yl

2-ethylhexan-1-yl, commonly written as 2-ethylhexyl, is a branched alkyl substituent used in organic chemistry. It is the group obtained when one hydrogen is removed from carbon-1 of 2-ethylhexane, an eight-carbon alkane that consists of a hexane backbone with an ethyl substituent at carbon 2. When this group attaches to another molecule through the C1 position, the result is the 2-ethylhexan-1-yl substituent.

In systematic naming, the substituent is called 2-ethylhexan-1-yl; in many contexts it is simply referred to as 2-ethylhexyl. The attachment point is the primary end carbon of the chain, yielding a primary alkyl radical. The 2-ethylhexyl group is one of several octyl isomers (C8H17) commonly used in industry.

This substituent is widely encountered as the alkyl portion of esters and ethers. It is especially prominent in commercial plasticizers and related materials, where it is derived from 2-ethylhexanol. Notable examples include di(2-ethylhexyl) phthalates and other diester or monoester derivatives used to impart flexibility to polymers.

Specific physical properties depend on the full compound containing the group; the 2-ethylhexyl fragment itself is a hydrocarbon alkyl group. Handling and safety guidelines follow those applicable to alkyl groups and the parent compound, with considerations varying by the overall chemical context.