How is this compound Meso?

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skyisblue

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According to my book, this molecule is considered meso because there's a plane of symmetry slicing between the H and OH group at the top.

BUT, I don't think this molecule can be meso because the H and OH group are not only NOT identical but they don't even match up in a mirror reflection.

What do you guys think?

Plus, let me know if you guys can't see where the dashes, solid lines and wedges are.....I need a new camera. :laugh:

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According to my book, this molecule is considered meso because there's a plane of symmetry slicing between the H and OH group at the top.

BUT, I don't think this molecule can be meso because the H and OH group are not only NOT identical but they don't even match up in a mirror reflection.

What do you guys think?

Plus, let me know if you guys can't see where the dashes, solid lines and wedges are.....I need a new camera. :laugh:

It is a meso compound and it is also achiral. If you draw it out in the form of a fischer projection, you would be able to see it much better.
 
expand CH2OH on the right side and see how it's identical to the left side. And it's really like OH and H that divides right and the left....I think
 
It is a meso compound and it is also achiral. If you draw it out in the form of a fischer projection, you would be able to see it much better.

Everything looks like a mirror image of the other except for the H and OH group on top. Yes, that is where the plane of symmetry splits the molecule.

I don't understand because having a plane of symmetry means that one half is a MIRROR image of the other half. Yet, how can H be a mirror image of OH? They are two totally different substituents.
 
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I think you are cutting H and OH molecules in half. resulting half of H molecule and half of OH molecules. Not H and OH.
 
Everything looks like a mirror image of the other except for the H and OH group on top. Yes, that is where the plane of symmetry splits the molecule.

I don't understand because having a plane of symmetry means that one half is a MIRROR image of the other half. Yet, how can H be a mirror image of OH? They are two totally different substituents.

this is why i said draw it out in fischer projection. If you look closely at the wedges and the dashed lines and you draw a line down the middle where it splits the molecule there is a mirror image because all the H's line up on the same side and the OH's line up on the other side. Ignore the H and OH on top and focus on the plane of symmetry.
 
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