some questions regarding nomenclature of organic compounds.

• onigiri

  24 Oct 09, 17:33

  Hi, I'm quite confused with the nomenclatures of some organic compounds.

  Hope the folks here will be able to help! =)

   

  

  Why is this compound named 3-ethyl-1,1-dimethylcyclopentane and not 1-ethyl-3,3-dimethylcyclopentane? Because, well, to me, it seems like ethyl is at position 1.

   

   

   

• UltimaOnline

  25 Oct 09, 01:09

  Disubstituted carbon takes priority over monosubstituted carbons, as far as the name with the lower numbering is preferred. So 1,1 & 3 is preferred over 1 & 3,3. IUPAC naming allows for a certain measure of flexibility (eg. phenylamine = aniline, methylbenzene = tolune, etc), because senseless dogma for the senseless purpose of senseless dogma aside, see the bigger picture - the IUPAC rules of nomenclature were designed to help, not hinder, humanity; as long as non-ambiguity is achieved, that's the entire point for the rules.
• onigiri

  25 Oct 09, 15:24

  thanks UltimaOnline! =)