Lec XXXVI

  Chem 1200

Angel C. de Dios

Coordination Cimpunds V

Zoom

For MA2B2C2, we saw already a pair of enantiomers when all like ligands are adjacent (cis-) to each other.

The other geometric isomers are:

(1)  all like ligands are opposite (trans-) to each other (This has no enantiomer since like ligands are trans-)

(2) A is trans to A (Again, no enantiomer since a pair of identical ligands are opposite each other)

(3) B is trans to B (no enantiomer)

(4) C is trans to C (no enantiomer)

The above exhausts all possibilities since we can only have either one pair of identical ligands trans- to each other or all three pairs trans-.

Thus, MA2B2C2 has a total of 6 isomers, with one pair enantiomeric.