What is the structure of 5,5-diethyl-2,2,3-trimethylheptane?
Answer:
I would start from the parent name, heptane. The prefix “hept” means \(7,\) so the main chain contains \(7\) carbons:
Then I would work from right to left in the name. The \(2,2,3 \text { – trimethyl }\) suggests that:
\(\text { tri } \rightarrow\) three duplicate branching groups
\(\text { methyl } \rightarrow \mathrm{H}_{3} \mathrm{C}-\) groups
The first two are on carbon-2 and the third one is on carbon-3.
So far, we fill it in as:
Lastly, we proceed to the leftmost part of the name. The \(5,5 \text { – diethyl }\) suggests that:
\(\mathrm{di} \rightarrow\) two duplicate branching groups
\(\text { ethyl } \rightarrow \mathrm{H}_{3} \mathrm{CCH}_{2}-\) groups
These are both on carbon-5.
So we get:
Lastly, since this is an alkane, the most saturated kind of hydrocarbon (relative to alkenes and alkynes), just fill in the rest of the branches with \(H\).
And this in reality looks like:
