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This passage is contradictory. I've boxed the section that confused me.

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Why would the book tell me to alphabetize substituents, only to clearly ignore its own rule about alphabetizing substituents?

Seems to me that "isopropyl" should come before "methyl," as the letter "i" is most definitely before the letter "m" in the alphabet. And the book makes no mention about ignoring the "iso-" prefix.


1) Should methyl come before isopropyl?

2) If so, why?


marked as duplicate by Jan, Klaus-Dieter Warzecha organic-chemistry Feb 12 '17 at 21:36

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The iso prefix is included in the alphabetic order.

For eg:- The compound Thymol has the following IUPAC name :- 2-Isopropyl-5-methylphenol and not 5-methyl-2-Isopropylphenol.

Therefore the name of your compound should be 4-isopropyl-2,3,3-trimethylheptane.


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