What is the IUPAC name of this organic compound?

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The discussion centers on determining the correct IUPAC name for a specific organic compound involving cyclopentadiene and an alcohol functional group. Participants propose several naming conventions, including 1-(cyclopent-1',4'-dienyl) methyl ethan-1-ol and 2-(cyclopent-1',4'-dienyl) propan-2-ol, while emphasizing the importance of proper numbering and prioritization of functional groups. There is debate over the correct numbering of the ring and the placement of substituents, with some suggesting that the main chain should dictate the numbering scheme. Ultimately, the consensus leans towards names that accurately reflect the structure while adhering to IUPAC rules. The conversation highlights the complexities of organic nomenclature and the need for clarity in chemical communication.
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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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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.
 
mjc123 said:
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.
 
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.
 
mjc123 said:
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.
 
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.
 
ChemSketch calls it 2-(cyclopenta-1,4-dien-1-yl)propan-2-ol.
 
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
 
NoahCygnus said:
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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NoahCygnus said:
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.
You have to start numbering from the foremost carbon attached to the functional group (which automatically becomes the main chain), number the first carbon of the cyclo group as 1 and know that it isn't included in the main chain as it is a 'substituent'
So the answer is 1-(Cyclopent-1,4 dienyl) 1-Methyl Ethan-1-ol. Feel free to ask any questions!
 
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