1-12
Chemistry
121, Winter 2008, LA Tech
IUPAC Nomenclature of Alkenes and
Alkynes
•name the longest continuous carbon
chain containing the multiple bond(s) (parent
chain). If cyclic, ring is the
parent.
•use
the infix -en- to show the
presence of a carbon-carbon double
bond
•use the infix -yn- to show the presence of a carbon-carbon triple
bond
•number the parent chain to give the
1st carbon of the double/triple bond the lower
number
•If
both double and triple are present and cannot have the same #, then double bonds take
priority.
•follow IUPAC
general rules for numbering and naming substituents
•for a cycloalkene, the double bond
must be numbered 1,2