85 topscore Exam 3 organic

[pistolpete007]

---

Members do not see this ad.

some plese explain this to me which of the following cyclohexane derivatives would be predicted to have the highest energy barrier for a chiar to chair interconverstion....


they gave the answer that had both tert-butyl groups in equatorila positions

but i think the answer should be the one with both methyl groups in axial position

doesnt higher energy=high delta H= less stable

less energy=small delta H = fairly stable

 

[TarheelKid24]

think of it like this....with both the t-butyl groups in very very stable equatorial positions, the structure will be very difficult to inter-convert due to its stability. If two methyl groups were in axial positions, they would "want" to convert to the more stable equatorial structure...

 

[pistolpete007]

right but the question is asking which has the highest energy barrier....isnt that the same thing as which has the highest energy=LEAST stable?

 

[TarheelKid24]

no, highest energy BARRIER....which REQUIRES the greatest energy to inter-convert. In other words, which is the MOST stable.

 

[pistolpete007]

ok got ya....what if the question was rewritten as which has the HIGHEST ENERGY

then would it be the one with both methyl in axial?