Page 1 of 1

Prioritizing substituents

Posted: Wed Mar 09, 2016 8:03 pm
by 504594108
When you have multiple substituents, do you prioritize the substituents for numbering by size or by alphabetical order? For example, if you have an ethyl and a propyl substituent on a cyclohexane, which one gets priority in numbering?

Re: Prioritizing substituents

Posted: Wed Mar 09, 2016 8:19 pm
by Michael Feingold 3B
you prioritize whichever one results in the lowest overall numbers in the name and you order the substituents in the name alphabetically

Re: Prioritizing substituents

Posted: Fri Mar 11, 2016 3:03 pm
by Lily Wei 1D
For substituents like ethyl and propyl, you would only prioritize alphabetically if there's a tie. Otherwise just number them to the lowest number. But for halogens like Cl or Br, you would prioritize by size but still list alphabetically in the name.