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Question: Are these compounds enantiomers?

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Attempt: The compounds given are mirror images. But if I rotated the three bonds in the third carbon (configuration will not change), I will get a meso compound (plane of symmetry) : enter image description here

So are these compounds enantiomers or meso compounds?

Aditya Dev
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  • Aren't there some restrictions for flipping/rotation of Fischer projections . – Sujith Sizon Oct 22 '15 at 10:58
  • Answer given is meso. At room temperature, rotation about any one single bond can take place. Interchanging 3 groups will not change configuration. – Aditya Dev Oct 22 '15 at 11:00
  • An unfortunate drawing of the original projections Place H at top and bottom easy to see it is an R,S configuration hence meso. – jimchmst Sep 22 '23 at 16:02
  • Realistically for compounds with more than 1 chiral centre, fisher projection is require to determine if compound is mesoisomer or enantiomers. If someone draws like that then dont rotate carbons to avoid confusion and just assume if it is meso or enantiomers based on diagram alone. – Luci Sep 22 '23 at 09:07

1 Answers1

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You are right, the 2 structures are equivalent and the substance has a plane of symmetry and is a meso compound. When in doubt, make a 3D model if possible.

iad22agp
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