Why would this be 5-ethyl-6,6-dimethyl-3-heptene when in aplhabetical order it should bebe: 6,6-dimethyl-5-ethyl-3-heptene? [duplicate]








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[Alphabetical order in nomenclature](/questions/46657/alphabetical-order-in-nomenclature)

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Closed 5 years ago.




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> Name the following compound:
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> [![enter image description here](https://i.stack.imgur.com/8v29h.png)](https://i.stack.imgur.com/8v29h.png)
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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**?




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



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> 5-**e**thyl-6,6-di**m**ethyl-3-heptene
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You can read up on this matter when following this [Wikipedia link](https://en.wikipedia.org/wiki/IUPAC_nomenclature_of_organic_chemistry).


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