Stereochemistry of Co III trien X2 complexes and resolution of the Trien Co III enantiomers.
1,238 words (approx. 5 pages) |
3 sources |
2000
From the Paper:
"In this experiment three Co(III)trienX2 complexes were prepared. These complexes were cis-alpha-[Co(trien)Cl2]Cl 1, cis-beta-[Co(trien)Cl2]Cl-0.5H2O 2, and trans-[Co(trien)Cl2]Cl-1.5H2O 3. The trien ligand is a tetradentate ligand, which is a strong field ligand. Once the trien ligand is coordinated to the metal the molecule's energy is lowered due to the chelate effect. The three complexes were studied using infrared and UV/Visible spectroscopy.
Also prepared in this experiment was the cation [Co(en)3]3+ which has two enantiomers. The ligand ethylenediamine is a strong field ligand, which is bidentate. This ligand also lowers the energy of the molecule through the chelate effect. The chelate rings remove a center of inversion, which removes the chance of an improper rotation axis and leads to an optically active molecule. The optical purity of the two enantiomers was calculated by measuring their specific rotation using a polarmetry apparatus."