What is the IUPAC name of this organic compound?

  • Thread starter NoahCygnus
  • Start date
  • #1
NoahCygnus
87
1
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.
 

Answers and Replies

  • #2
mjc123
Science Advisor
Homework Helper
1,136
577
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
NoahCygnus
87
1
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.
 
  • #4
mjc123
Science Advisor
Homework Helper
1,136
577
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
NoahCygnus
87
1
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.
 
  • #6
mjc123
Science Advisor
Homework Helper
1,136
577
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
Mentor
28,780
3,258
ChemSketch calls it 2-(cyclopenta-1,4-dien-1-yl)propan-2-ol.
 
  • #8
Argho Sen
1
0
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
Keshav Tibrewal
1
0
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]
 

Hot Threads

Recent Insights

Top