O-cehm question

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howui3

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Can someone explain how E is the correct answer. I understand how hydrogenation occurs, but aren't the two products in choice E identical?

I chose A, which has the syn addition of the H's.

Thanks for the help.
 

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howui3 said:
Can someone explain how E is the correct answer. I understand how hydrogenation occurs, but aren't the two products in choice E identical?

I chose A, which has the syn addition of the H's.

Thanks for the help.

Maybe it's just me, but even when I enlarged the image I couldn't make out the question. Sorry.
 
Choice A: cis 1-ethy, 2-methyl cyclohexane

Choice E:the first one is the same as A, and the next one has the ethy and methy groups switched. So if you flip it (mirror image) to me it looks like the same product.


The SDN will only allow a tiny ass attachment. hence my pic.
 
typo, A is supposed to be cis 1-ethyl, 2-methylcyclohexane
 
howui3 said:
Can someone explain how E is the correct answer. I understand how hydrogenation occurs, but aren't the two products in choice E identical?

I chose A, which has the syn addition of the H's.

Thanks for the help.
The resolution on that picture is horrible. Can't make out a word. Sorry.
 
i believe the hydrogens can add from top or bottom - it's a stereo specific reaction 😉

and the credited choice is indeed, E 😀
 
fannian said:
i believe the hydrogens can add from top or bottom - it's a stereo specific reaction 😉

and the credited choice is indeed, E 😀

THE ANSWER HAS TO BE 'E' because there is no symmetry in the molecule. IF u take second molecule of E, and try to fit onto A, if u do get the hydrogens in the right place, u switch the positions of the groups that lie to the left and right of it. So, all in all...E does contain 2 diff. molecules. Sorry for my stupidity and getting overconfidence in posting a last message. If you don't get what i am saying, let me know. I'll try and word it better.
 
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