Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: _Weirdo_0.o on October 14, 2012, 07:15:38 PM
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There's a picture of the problem from one of my quizzes. I have the solution but don't understand it.
Can anyone tell me why the longest chain is that cyclohexadexane? Are you just supposed to know that it's a cyclo with huge substituents? The answer is:
3,3-dibromo-1-sec-butyl-6-tert-butyl-2-heptyl-7-cycloheptyl-13-isobutyl-14-isopropyl-5,12-dimethyl-10-neopentyl-8-pentadecyl-4-propylcyclohexadecane
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Because the longest carbon chain is the cyclohexadecane (16 carbons) its in the middle
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Here is a picture for clarity
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During the test, I didn't see the cyclo so I started at the end of that pentadecane ::)
But, the rule is: look for the longest CONTINUOUS chain? My prof never specified.. that, or I wasn't paying attention Dx
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yea the rule is look for the longest continuous chain.
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Thanks again! :)
Also, can you please explain neo-pentyl and iso-pentyl's names? Like, I understand that tert-butyl uses "tert" because the middle Carbon is attached to 3 other carbons. But, why neo and iso?
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It depends on how many carbons are bonded to the alkyl group: alkyl groups with the prefix iso has a secondary carbon, alkyl groups with the prefix tert has a tertiary carbon, and alkyl groups with the prefix neo has a quaternary carbon.
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You are probably going to ask how to identify primary, secondary, tertiary and, quaternary.
primary - bonded to one carbon atom
secondary - boned with two carbon atoms
tertiary - bonded with three carbon atoms
quaternary - bonded with four carbon atoms
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Thanks so much :)
I'll probs be back with more questions haha
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here was the picture I forgot to post :P
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Thanks :)