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According to what I took (look for the longest chain, start close to the branches, etc etc) I see two paths I could follow to give me a hexane. One where you go through the carbon in the methyl, and the other by going through two carbons in the ethyl.

In one case I'm left with a diethyl and a methyl and in the other I'm left with an isopropyl and one ethyl. Which of these is correct?

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    $\begingroup$ In such cases (when 2 or more possible routes give the same number of carbons in the parent chain) we look for which of the possibilities has the highest branching. The one with the highest branching is considered as the parent chain. In your case, the chain you must consider as the parent chain is the one having diethyl and methyl as its branches. $\endgroup$ – Raviraj Bhosale Jun 9 at 1:26
  • $\begingroup$ Thank you! Must've missed that somewhere. any good simplified sources on IUPAC naming rules? $\endgroup$ – user109634 Jun 9 at 2:05
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Taken from the answer to In Parent chain choosing should one consider longest chain or chain with more substituents? by Loong.

From the Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book)

P-45.2.1 The preferred IUPAC name is based on the senior parent structure that has the maximum number of substituents cited as prefixes (other than ‘hydro/dehydro’) to the parent structure.

Therefore in this case, the diethyl and methyl make up 3 substituent groups whereas the ethyl and isopropyl group only make up 2 substituents. Therefore the chain that has the diethyl and methyl group needs to be taken as the parent chain here.

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Therefore, the PIN of this compound is 3,3-diethyl-2-methylhexane.

As a side note: A brief set of the IUPAC rules can be found here

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