Fe (III) complexes of a bis-benzimidazolyl diamide ligand: Spectral and Catalytic studies

Abstract A new tetradentate bis benzimidaozlyl diamide ligand N,N′-Bis (benzimidazol-2-yl-methyl)-hexane-1,6-dicarboxamide (GBSA) has been synthesized and utilized to prepare new Fe(III) complexes with exogenous anionic ligand X = Cl − and NO 3 − . Isomer shift values are in the range found for Iron in the +3 oxidation state while Quadrupole Splitting indicates large distortion from a six coordinate geometry, a finding supported by low temperature EPR work. The E 1/2 values are found to be quite cathodic indicating stability of the Iron (III) complexes. The oxidation of alcohols was investigated using [Fe(GBSA)Cl 3 ] as the catalyst with TBHP as an alternate source of oxygen. The respective carbonyl products have been isolated and characterized by 1 H NMR, electronic spectroscopy, mass and IR spectral studies.