The IUPAC name of the following compound is: HC C-CH2- OH |CH-CH2-CH=CH2
- 4-Hydroxyhept-6-en-1-yne
- Hept-1-en-6-yn-4-ol
- Hept-6-en-1-yn-4-ol
- 4-Hydroxyhept-1-en-6-yne
Answer
(2) Hept-1-en-6-yn-4-ol
Solution
Principal functional group: –OH (suffix -ol); parent chain = 7 C atoms containing both multiple bonds.
From either end, –OH is at C-4, and the multiple bonds get the locant set 1, 6.
there is a tie, the double bond gets the lower number:
1CH2= 2CH- 3CH2- 4CH(OH)- 5CH2- 6C 7CH
Name: Hept-1-en-6-yn-4-ol ('-en' is written before '-yn'; 'Hydroxy' is not used as –OH is the principal group).
Answer: (2)