Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: Mager on February 10, 2017, 08:21:20 PM
-
I have given this assessment some time and consultation with various sources and can not seem to get a definitive answer. Professor says one thing and book says otherwise. Please view the attachment photo to see my work and assist in determining the proper name of the compound. This is primarily in regards to the configuration being assigned and not necessarily the nomenclature.
-
Forget about the book and your professor for a minute, what do you think and why?
-
My understanding would consider the double bonded carbon at position 2, to take precedence over the carbon in position 6 with a methyl substituent. I say this because I view this carbon as being attached to the carbon in the 1 position, which breaks the tie between it and the carbon in the 7 position. Carbons 1 has a double bond (counting as 2 C for this purpose) and is also bound to another carbon, while carbon 7 is bound directly to only a single other carbon. As a result I would assign the carbon with the double bond a higher priority (2nd) when determine the priority groups stemming from the chiral center at the carbon in position 4.
-
In your opinion
C-C-H has priority over CH3-C-H ?
-
After rethinking this a bit more. I would say that the carbon in the 6 position would actually take precedence over the carbon in position 2. This would be because the carbon in position 6 is bound to 2 "actual" carbons, whereas the carbon in position 2 is bound to only 1 real carbon and a "phantom" carbon resulting from the double bond. The idea would be that the real carbon wins priority over the "phantom" carbon and therefor the carbon in the 6 position is priority #2 for the chiral center at carbon in position 4.