Oxidation of substituted alkynes catalyzed by a non-heme iron(III) bis benzimidazole diamide complex as catalyst under ambient conditions

Abstract

Bis-benzimidazole diamide ligand,<b style=""> </b>N,N′- bis(2-methylbenzimidazolyl) hexanediamide [GBHA = L], and its Fe(III) complexes have been synthesized. The Fe(III) complexes have been analyzed for the composition [Fe(L)X₃].nH₂O where X is an exogenous anionic ligand (X=Cl¯, NO_3­¯) and characterized by IR, UV-visible, cyclic voltammetry and EPR spectroscopy. Low temperature EPR spectra have been obtained for the complexes that indicate rhombic geometry environment in solution state. Oxidation of substituted alkynes has been investigated using these Fe(III) complexes as catalyst with TBHP and H₂O₂ as an alternate source of oxygen. The isolated products have been characterized by GC-MS.