[Shadow]

Is there a plane of symmetry in (1R,2S)-1-bromine-2-methylcyclohexane? I think that there is, so it isn't optically active. It should be meso, but I need a confirmation from someone else.

[sjb]

Is there a plane of symmetry in (1R,2S)-1-bromine-2-methylcyclohexane? I think that there is, so it isn't optically active. It should be meso, but I need a confirmation from someone else.

Can you draw a picture showing where your proposed plane of symmetry is?

[discodermolide]

Surely meso compounds have the same substituents on adjacent carbons?

[Shadow]

So it is not meso. Then I have the (1S,2R) isomer, too?

[discodermolide]

Yes, I would expect as well.

[Shadow]

There are four compounds then: (1S,2R), (1R,2S), (1R,2R), (1S,2S) and not two are superimposable, right?

[discodermolide]

Yes that's correct, 4 possible diastereoisomers, two enantiomeric pairs.

[Rutherford]

Have to ask, if the substituents were the same, these would be meso?

[discodermolide]

Have to ask, if the substituents were the same, these would be meso?

Look here:
http://en.wikipedia.org/wiki/Meso_compound