[Ephraim]

One final question.

In our class, we had discussed dissociative mechanisms of octahedral compounds and had said that the pi orbitals of a ligand can stabilize both the trigonal bypyrimidal transition state and the square pyramidal transition state. It was implied that this "trans" effect preferred to stabilize the trigonal bypyrimidal transition state.  Is there a reason for this? If so, does it have to do with better overlap of orbitals? Further, how can one predict which transition state it will go to?

Thank you

[Cat in the Lab]

better overlap of orbitals really help stabilizing. that's like how two single bond is stronger than one double and . however, i'm not sure if it's related to the stabilization you've mentioned.