cyclohexenyl

Cyclohexenyl is a term used in organic chemistry to denote a substituent derived from cyclohexene by removal of one hydrogen. The cyclohexenyl moiety has the empirical formula C6H9 and is typically linked to another molecule through one of the ring carbons, most commonly at C1, giving a cyclohex-1-en-1-yl substituent. Because the parent ring contains a carbon–carbon double bond, the cyclohexenyl group remains unsaturated and can participate in a variety of reactions characteristic of alkenyl-containing fragments.

Nomenclature can refer to cyclohex-1-en-1-yl, cyclohex-2-en-1-yl, or other cyclohexene-derived linkages, depending on the site of attachment. In systematic naming, the exact position of attachment is specified to indicate the point of connection (for example, cyclohex-1-en-1-ylphenyl).

Reactivity and uses: The presence of a C=C bond makes cyclohexenyl derivatives reactive toward electrophilic addition to the double bond, radical reactions at allylic positions, and various oxidation or cross-coupling processes used in organic synthesis. Cyclohexenyl groups can act as ligands in organometallic chemistry or be incorporated into polymers as unsaturated side chains.

See also: cyclohexene, cyclohexyl, allyl group.