What is the IUPAC name of this organic compound?

  • Thread starter NoahCygnus
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  • #1
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Well I have two possible answers, it's either 1-(cyclopent - 1', 4'- dienyl) methyl ethan-1-ol or 1-methyl - 1 - (cyclopent-1',4'-dienyl) ethan-1-ol.
Unfortunately the answer wasn't provided in the textbook.
 

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  • #2
mjc123
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What is 1-methylethanol?
I would find it simplest to name it 2-(2-hydroxyprop-2-yl)cyclopentadiene, but that doesn't name it as an alcohol so I suspect is not correct.
Alternatively, 2-(2-cyclopentadienyl)-2-propanol?
Note that (i) you must specify the position of substitution on the ring; (ii) the ring is 1,3-cyclpoentadiene, not 1,4. Actually you can just say cyclopentadiene, because there is only one possible cyclopentadiene.
 
  • #3
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What is 1-methylethanol?
I would find it simplest to name it 2-(2-hydroxyprop-2-yl)cyclopentadiene, but that doesn't name it as an alcohol so I suspect is not correct.
Alternatively, 2-(2-cyclopentadienyl)-2-propanol?
Note that (i) you must specify the position of substitution on the ring; (ii) the ring is 1,3-cyclpoentadiene, not 1,4. Actually you can just say cyclopentadiene, because there is only one possible cyclopentadiene.
244529

Nomenclature rules state that the functional group has a higher priority than a ring or double bonds, so the main chain will be the one marked by blue. I screwed up in the first try, I didn't see that there was a propane chain. I redid the problem and came with the answer 2-(cyclopent-1',4'-dienyl) propan-2-ol.
 
  • #4
mjc123
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The numbering of the ring atoms is such as gives the lowest numbers to the double bonds (not such as puts the substituent on atom 1). Thus it is cyclopenta-1,3-dienyl and the substituent is on atom 2.
 
  • #5
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The numbering of the ring atoms is such as gives the lowest numbers to the double bonds (not such as puts the substituent on atom 1). Thus it is cyclopenta-1,3-dienyl and the substituent is on atom 2.
cyclopenta-1,3-dineyl? 1,3? I don't get how you numbered the ring, you have to number the carbon of the ring attached to the main chain as 1'. See diagram. There is no double bond on 3' carbon of the ring.
 
  • #6
mjc123
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Maybe I'm thinking of cyclopentadiene as the base compound. To me, that's a cyclopentadiene with a substituent on atom 2. If IUPAC thinks differently, they're wrong, that's all I can say.
 
  • #7
Borek
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ChemSketch calls it 2-(cyclopenta-1,4-dien-1-yl)propan-2-ol.
 
  • #8
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I think it's 1-(cyclopent-1,4-dienyl) 1-methyl-ethanol.
Cyclo is starting with "C" and methyl is starting with "M" When there are two substituents, you write them alphabetically
 
  • #9
View attachment 244518
Well I have two possible answers, it's either 1-(cyclopent - 1', 4'- dienyl) methyl ethan-1-ol or 1-methyl - 1 - (cyclopent-1',4'-dienyl) ethan-1-ol.
Unfortunately the answer wasn't provided in the textbook.
IUPAC RULE IS TO WRITE SUBSTITUENTS ALPHABETICALLY THEREFORE IT WOULD HAVE BEEN THE FIRST ONE BUT YOU MADE SLIGHT MISTAKE THE CORRECT NAMES ARE:-
2-(cyclo penta-1', 4'- dienyl) propan-2-ol [most detailed]
or 2-(cyclo penta-1, 4- dienyl) propan-2-ol [without ']
or 2-(1,4-cyclo pentadienyl)-2-propanol [simplest]
 
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