Structure and catalytic activity of a new iron(II) complex with a tetradentate carboxamide ligand: The effect of the outer-sphere donor on the chemoselectivity of the metal complex catalyst

Abstract

The interaction between Fe(ClO4)2 or Fe(OTf)2(MeCN)2 and 2 equiv of the potentially tetradentate ligand bis(2-pyridyl)methyl-2-pyridinecarboxamide (Py2CHNHCOPy, tpcaH) yields the iron(II) complex [FeII(tpcaH)2]X2 (X = ClO4, OTf), in which, according to X-ray crystallography data, tpcaH is facially coordinated to the iron atom as a tridentate ligand through the carbonyl group and two pyridyl donors of the bis(2-pyridyl)methylcarboxamide moiety and the third pyridyl group is uninvolved in coordination. The oxidation of saturated and unsaturated hydrocarbons with hydrogen peroxide involving this complex has been investigated. The presence of the uncoordinated nitrogen donor in the outer coordination sphere of the complex exerts a crucial effect on it catalytic properties.