# How are t-butyl substituents named according to IUPAC nomenclature?

What is the IUPAC name of this structure?

I've actually came up with two names, the first one is "1-tert-butyl-5-heptyl-2-propylcyclononane" and the other one is "1-(1,1-dimethylethyl)-5-heptyl-2-propyl-cyclononane". I'm confused which one is right or if both are correct.

• @KarstenTheis I've actually came up with two names, the first one is "1-tert-butyl-5-heptyl-2-propylcyclononane" and the other one is "1-(1,1-dimethylethyl)-5-heptyl-2-propyl-cyclononane". I'm confused which one is right or if both are correct. – user76215 Mar 26 at 17:55
• So your question is not about how to name it, but rather whether the tBu group should be written as "tert-butyl" or "1,1-dimethylethyl". – orthocresol Mar 26 at 18:02
• Note also that there should not be a hyphen directly before cyclononane; one of your proposed names is correct in this regard and the other isn't. – orthocresol Mar 26 at 18:06

According to Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 (Blue Book) (P-57.1.2), the preferred prefix for $$\ce{-C(CH3)3}$$ is "tert-butyl".