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Why are ethers not considered as functional groups in IUPAC nomenclature?

Let us consider the following example:

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The PIN for this compound is 2-ethoxy-1,1-dimethylcyclohexane. And we get this by first point of difference as ether is also considered as a substituent here.
But ethers do confer specific properties to the compound. They are studied as a separate functional group. Yet they aren’t given the preference in nomenclature in the absence of any other functional group too. Why is this so? Is it just a convention or is there a reason behind it?


PS: I checked this similar question on our site but it doesn’t answer my question as to why ethers aren’t functional groups when it comes to naming.

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The priority order for functional groups is as follows:

Radicals > Anions > Cations > Zwitterionic compounds > Acids (In the order -COOH, -COO(O)H, S-derivatives, Se-derivatives, Sulphonic acids, Phosphonic acids, etc)> Anhydrides > Esters > Acid halides > Amides > Hydrazides > Imides > Nitriles > Aldehydes > Ketones > Alcohols and Phenols > Amines > Imines > hydrazine > Phosphanes > Alkene > Alkynes > Alkanes> Ethers > peroxides > Halo, Nitro, Nitroso, Alkoxy > Oxiranes

Functional groups such as Ethers and Nitro-groups are way down the order and will not be the primary functional group more often than not, the reason behind them be named as substituents.

In your question, the alkane group is given priority over the ether as per the above-mentioned priority order for functional groups. Thus the name given is 2-Ethoxy-1,1-dimethylcyclohexane.

Let's say instead of the 2 methyl groups over there, you had a nitro group, then the ether would have become the principal functional group and the nitro group being the substituent. There's no rule saying that ethers are always to be named as substituents as per my knowledge.

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  • $\begingroup$ @J_B892 I'm not sure if I agree with this explanation. The question still remains as it was. See: alkanes are not a functional group, whereas nitro and ether are a functional group. Yet the former is given a higher priority over the latter. So, what was the need to separate ether and nitro from the rest of the functional groups (which are above alkanes), and place them below the alkanes instead? $\endgroup$ – Gaurang Tandon Mar 30 '18 at 9:07
  • $\begingroup$ Alkanes or more precisely alkyls are functional groups. I have also mentioned it in the priority order. Please check $\endgroup$ – J_B892 Mar 30 '18 at 9:16
  • $\begingroup$ “In your question, the alkane group is given priority over the ether as per the above-mentioned priority order for functional groups.” No. The name 2-ethoxy-1,1-dimethylcyclohexane is simply based on the usual substitutive nomenclature. The seniority order is not relevant in this case since no functional group is expressed by suffix or class. Compare also the analogous compound 1,1-diethyl-2-methoxycyclohexane. $\endgroup$ – Loong Jun 22 '18 at 12:41
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    $\begingroup$ “Let's say instead of the 2 methyl groups over there, you had a nitro group, then the ether would have become the principal functional group and the nitro group being the substituent.” No. That compound would still be named by usual substitutive nomenclature as 1-ethoxy-2-nitrocyclohexane. $\endgroup$ – Loong Jun 22 '18 at 12:43

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