cis and transe in cyclohexane has what conformation in chair?

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tmandudeguy

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When you have a planar diagram of a cyclohexane and its cis or transe how do they respectively look like in the chair conformation? Logic would dictate that both substituents would both be axial or equatorial in the chair if they were cis in the planar cyclohexane. Is this correct?

Thank You
 
no.
Next to each other or odd # apart (1,2 or 1,4 or whatev) would have 1 eq and 1 axial for cis and 2 eq and 2 axial for trans.
Even # apart would have 2 eq or 2 axial for cis and one of each for trans.
 
Draw cyclohexane in a chair conformation and leave lines where every bond can be formed. Now put substituents and the positions you want. This is meant to help you see see how cis and trans inherently tells you little about axial or equatorial. You need to visualize.

Notice, that if you have a 1,2 disubstituted cis cyclohexane, then one substituent will be axial and the other will be equatorial. If you have a 1,3 disubstituted cis cyclohexane they both will either be axial or equatorial. Continue playing with your drawing till this makes sense (or keep on drawing different rings, but show all the bonds until you can easily visualize them.)

Cis means they are on the same "side" of the ring. trans means they are on opposite "sides" of the ring. It does not inherently tell you axial or equatorial positions.
 
So could someone please confirm this

Cis 12 - 1 axial 1 equatorial
Trans 12 - both axial/equatorial

Cis 13 - both axial/equatorial
Trans 13 - 1 axial 1 equatorial

Cis 14 - 1 axial 1 equatorial
Trans 14 - both axial/equatorial

Cis 15 - both axial/equatorial
Trans 15 - 1 axial 1 equatorial

Cis 16 - 1 axial 1 equatorial
Trans 16 - both axial/equatorial
 
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So could someone please confirm this

Cis 12 - 1 axial 1 equatorial
Trans 12 - both axial/equatorial

Cis 13 - both axial/equatorial
Trans 13 - 1 axial 1 equatorial

Cis 14 - 1 axial 1 equatorial
Trans 14 - both axial/equatorial

Cis 15 - both axial/equatorial
Trans 15 - 1 axial 1 equatorial

Cis 16 - 1 axial 1 equatorial
Trans 16 - both axial/equatorial

Confirmed. Except wtf @ cis/trans 1,6? You know there are only 6 carbons in cyclohexane?
 
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