IUPAC Names of Organic compounds

[CroSinus]

Homework Statement

Name the following compound according to the IUPAC rules:

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Homework Equations

The Attempt at a Solution

Comment on my attempt, please.
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[baldbrain]

Homework Statement

Name the following compound according to the IUPAC rules:View attachment 228511

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Homework Equations

The Attempt at a Solution

View attachment 228512
Comment on my attempt, please.
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You select the end from which the more substituted carbon comes first. So which end is it?
Also, you don't need to do the sum for aliphatic compounds, that's only for cyclic compounds.

 

[CroSinus]

Strange rules. Would not be better if I took into consideration all substituents? In other words shouldn't I pay attention to the sum of all substituents?
Well, strange rules!

Thank you for helping me.
Cro

 

[baldbrain]

Actually, your doubt prompted me to do a bit of a search on it, and I'm astounded too.
https://chem.libretexts.org/LibreTexts/Athabasca_University/Chemistry_350:_Organic_Chemistry_I/Chapter_4:_Organic_Compounds:_Cycloalkanes_and_their_Stereochemistry/4.1_Naming_Cycloalkanes
http://www.chem.ucalgary.ca/courses/351/WebContent/orgnom/main/dontsum.html
Here, we have 2 articles, both from trusted sites, Chemistry LibreTexts and University of Calgary.
The first says that 'summing locants' is valid, while the other says that there is no such thing anywhere in the IUPAC nomenclature (even if we've been taught so elsewhere!) and also provides a valid justification for it.
Logically speaking, it makes sense that the higher priority substituent should get the lower number, and that should be it; which questions the validity of the 'lowest sum rule' altogether! The UCalgary standpoint appeals to me more.


This needs attention from another expert. Discuss this anomaly with your professor

 

[baldbrain]

@TeethWhitener @Borek Can you take a look at this?

 

[TeethWhitener]

I don't spend much time on IUPAC (I've mentioned before on this forum that I think a lot of the conventions are illogical and unhelpful). That said, if I have to name a compound, I usually cheat by going to some chemical database that names the compounds automatically (PubChem, SciFinder, and Sigma are all pretty good). In this case, I used the PubChem structure search, which returned this little nugget:
https://pubchem.ncbi.nlm.nih.gov/compound/23333527

 

[Borek]

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