Triple bonds priority rules

Before leaving this section, note also that there is a bit of a trick to rule 3 as well. For priority determination purposes, double and triple bonds are changed so that both atoms involved are doubled or tripled. For example, a carbon doubly bonded to another carbon is changed to a carbon singly bonded to two carbons. 

Rule 3. Finally, it is necessary to consider the manner in which double bonds are dealt with in the priority sequence. If a double bond, or triple bond, is present, the specific atom(s) attached to the double bond are considered to be doubled or tripled respectively. 

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