JACS Directory invites you to share your innovations through www.jacsdirectory.com

Article – Journal of Advanced Chemical Sciences

Journal of Advanced Chemical Sciences, Volume 2,Issue 2,2016 Pages 255-258

Structural Characterization of Iron (III)-Salen Complexes Containing Axial Ligands – A Computational Study
P. Kavitha, P. Karuppasamy*

The proximal axial ligands in non-heme enzymes play an important role in tuning the reactivities of iron (III)-salen complexes in various oxidation reactions. The present study reports the influence of axial ligands: Br-, Cl-, F-, I-, H, CH3, OCH3, CH3CN, CN, NO2, ClO4, OOCCF3, SO3H, SO3CF3, N3 and pyridine in the structural aspects of iron(III)-salen complexes. Computational study of iron (III)-salen complexes containing these axial ligands gives the bond lengths and bond angles in the optimized structures. These values are in accordance with the reported X-ray values. The calculated energy of spin multiplicity sextet (S = 6) obtained from DFT( Density Functional Theory) lies below doublet (S = 2) and quartet (S = 4) surfaces by 13.7 and 5.8 kcal mol−1 respectively, indicating that sextet is more stable compared to the other two multiplicities for all the iron(III)–salen complexes. Indeed the structural elucidation of the iron (III)-salen complexes and the corresponding oxo-iron derivatives is of paramount importance to understand the mechanism of important biological oxygenation reactions. These electron donating axial ligands in the complexes stabilize the iron centre and are responsible for the weakening of the Fe-O bond in the transition state of the oxygenation reactions.

Keywords: Axial Ligand; Effects Iron (III)-Salen Complex; DFT Study;