RareEarth - 18-4-2015 at 10:22
I couldn't find much information on this. I found some vague mentions in various online texts that meso compounds were "rarer" to occur, but nothing
to explain why this would be.
Do meso compounds occur at a similar ratio as the other enantiomers, if for instance a diketone was aminated?
With an occurrence distribution like this:
R:S 25% (meso)
S:R 25% (meso)
R:R 25%
S:S 25%
Or is there something about the Meso configurations that make them sterically unfavored in forming?
RareEarth - 23-4-2015 at 18:56
I'm surprised nobody has commented yet. Can this be moved to the Organic Chemistry forum?
Chemosynthesis - 23-4-2015 at 19:43
Yes, to an extent this can be predicted due to sterics. Check out Cram's rule. This should make much more sense in that context. I believe these were
the two original citations: JACS 1952, 74, 5828 and JACS 1959, 81, 2748.
This has been extended with Prelog and Horeau rules, and has specifics built into various models with their own rules including Karabatsos',
Felkin-Ahn's, Cieplak's effect, Baldwin’s Rules, the Bürgi-Dunitz's Angle, and I am sure many more I never heard of, depending on your substrates.