Meso Compounds with an odd number of chiral centers

[thefan]

I was learning about chirality in my organic chemistry class when we were talking about meso compounds. The professor stated that for a compound to be meso, you needed there to be two or more chiral centers. After thinking about it for a while, I can come up with abstract structures for meso compounds with 2, 4, ..., 2n chiral centers, but can't come up with one that has 2n+1 chiral centers. Is it possible to have a compound with an odd number of chiral centers that is meso?

 

[sjb-2812]

I was learning about chirality in my organic chemistry class when we were talking about meso compounds. The professor stated that for a compound to be meso, you needed there to be two or more chiral centers. After thinking about it for a while, I can come up with abstract structures for meso compounds with 2, 4, ..., 2n chiral centers, but can't come up with one that has 2n+1 chiral centers. Is it possible to have a compound with an odd number of chiral centers that is meso?

Sure, try (1R, 2S,4r)-1,2,4-cyclopentanetriol or similar.

 

[DrDu]

Compare also this older thread:


https://www.physicsforums.com/showthread.php?t=369296

 

[akmethod]

you have to be careful with how you through around the terms "stereocenter" and "chiral center." If your instructor said "A meso compound cannot have 2n+1 number of CHIRAL centers," then they are correct. It would be incorrect to say "a meso compound that contains STEREOcenters must have 2n stereocenters." In other words, these terms do not have the same meaning. All chiral centers are stereocenters, and not all stereocenters are chiral centers. the term "stereocenter" or "stereogenic center" means that swapping two groups on that center would give a different stereoisomer, whereas "chiral center" means that the atom doesn't occupy a molecular plane of symmetry (4 different substituents bonded to the atom).