Destroyer'15 Q27 Most Stable Newman

[BabyBombers24]

Advertisement - Members don't see this ad

In the 2015 DAT DESTROYER Q. 27
This question requires you to determine the most stable Newman, and I get that the answer is E bc the Gauche interactions between Br-Br isn't as reactive as Br-CH3, but in the solution it says that between B and D (eclipsed models), B. is MOST UNSTABLE (Br-Br close proximity to each other). Considering the reasoning behind the gauche interactions of Ch3 and Br, why doesn't this apply for the eclipsed conformation of answer choice D (CH3 and Br close proximity). I would think D would be the most unstable since the 2 atoms are larger interactions. Can anyone clarify? Thank you!

 

[ZOZO_SAGA]

In the 2015 DAT DESTROYER Q. 27
This question requires you to determine the most stable Newman, and I get that the answer is E bc the Gauche interactions between Br-Br isn't as reactive as Br-CH3, but in the solution it says that between B and D (eclipsed models), B. is MOST UNSTABLE (Br-Br close proximity to each other). Considering the reasoning behind the gauche interactions of Ch3 and Br, why doesn't this apply for the eclipsed conformation of answer choice D (CH3 and Br close proximity). I would think D would be the most unstable since the 2 atoms are larger interactions. Can anyone clarify? Thank you!

I believe it's a typo, cause on my DAT destroyer 2017 version question 32 (same question as yours) says that D is the most unstable not B. Which you're totally right.