Chapter B, Problem B.8P

Interpretation Introduction

Interpretation:

The structures for the given compounds are to be written.

Concept introduction:

For a molecule that has both $\text{C=C and C}\equiv \text{C}$ groups, the IUPAC name indicates both the groups, and the molecule is called ‘enyne.’ The root name is established as the longest carbon chain or largest carbon ring that contains both groups, and the suffix is changed to enyne. The numbering system must be chosen so as to give the minimum locator number for each successive $\text{C=C and C}\equiv \text{C}$ group. The $\text{C=C and C}\equiv \text{C}$ groups are given equal priority unless there is a tie between the two numbering systems. If there is a tie, the tie is broken by giving priority to the $\text{C=C}$ group. The locator number of $\text{C=C}$ groups is added immediately before en, and the locator number of $\text{C}\equiv \text{C}$ groups is added immediately before yne. Immediately before the ene or yne suffix, the letter ‘a’ is added, followed by the above set of locator numbers, and then the prefix di, tri, etc. is added to specify the number of double or triple bonds. The substituents attached to the root are named in alphabetical order.