Interchanging "Axial" and "Equatorial" Atoms within the Ligands of a Chiral Sn(II) Complex

A: Calculated Ground State Structure for Sn(NHCHNH)2
Viewing tools:


Impose a orange/blue color scheme to follow the atoms undergoing exchange:
Begin "equatorial" and become "axial" orange
Begin "axial" and become "equatorial" blue


To focus on the coordination sphere about Sn

and examine the fragment by moving the molecule with your mouse

Note that this process intercoverts the
two chiral forms of this molecule. In other words,
it racemizes the molecule.

 Calculated Transition State
Viewing Tools:


Tools to view the "Berry" Exchange Mechanism
  1. Turn
  2. Displacement
  3. then
    Compare to A
  4. View one Cycle of the Vibration:

    Compare final point (b) to B
  5. of "Berry" Character:
  6. View
B: Calculated Ground State Structure for Sn(NHCHNH)2
Note that this is the enantiomer of A
Viewing tools:


Impose a orange/blue color scheme to follow the atoms undergoing exchange:
Begin "equatorial" and become "axial" orange
Begin "axial" and become "equatorial" blue


To focus on the coordination sphere about Sn

and examine the fragment by moving the molecule with your mouse

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