Name the following compound:

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Why would this be 5-ethyl-6,6-dimethyl-3-heptene when in alphabetical order it should be 6,6-dimethyl-5-ethyl-3-heptene?

  • $\begingroup$ Actually, since 1993, the correct name according to IUPAC recommendations is 5-ethyl-6,6-dimethylhept-3-ene. $\endgroup$ – Loong Oct 10 '17 at 18:34

The prefixes di-, tri-, etc. are not considered when determining the alphabetical order of the substituents. So the order is actually determined like this:


You can read up on this matter when following this Wikipedia link.


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