[Makaroo]

Howdy folks. I've got a question: Draw a constitutional Isomer (of the molecule below) of the following molecule that is also a meso compound.

I can't get anything. As soon as I make it symmetrical, I can't find a stereocenter. Do you guys have any suggestions?

[karlosshughes]

Two compounds are meso if their mirror images are superimposable on one another.

Thus, all the stereogenic centres must have the opposite configuration, that is the protons and R group which are all "up" must all be "down" in the other meso form, so that, when placed on top of this compound, there is no difference.

Hope this helps.

[sjb]

Howdy folks. I've got a question: Draw a constitutional Isomer (of the molecule below) of the following molecule that is also a meso compound.

I can't get anything. As soon as I make it symmetrical, I can't find a stereocenter. Do you guys have any suggestions?

Perhaps focus on the 5:5 system - there is only 1 nitrogen so there is only really one place it can go, then perhaps orientate the methyls? There are a number of answers available here...

[movies]

Perhaps focus on the 5:5 system - there is only 1 nitrogen so there is only really one place it can go, then perhaps orientate the methyls? There are a number of answers available here...

That's not really true.  It could be at any spot where it would be in a mirror plane, so there are 4 options for the N in the [5–5] system.  Also, there is nothing that says that the [5–5] system has to remain intact!


There are many possible answers to this question, so just keep trying to move groups around.