Reactivity and Catalysis with Two-Coordinate Metal Complexes
On the basis of our observation that the simple iron amido complex Fe[N(SiMe3)2]2 catalyzes carbonyl hydrosilations,1 a more comprehensive program was initiated to explore the fundamental chemical and catalytic properties of two-coordinate first-row metal complexes. Although this relatively new class of complexes has attracted attention for their exceedingly low-coordinate structures, and more recently for their magnetic properties, very little is known about their chemical reactivity. The 2-coordinate bis(amido) Ni[N(SiMe3)DIPP]2 (DIPP = 2,6-iPr2C6H3), with an unusual, planar (eclipsed) (C)(Si)N–Ni–N(Si)(C) core, was found to be an efficient, selective catalyst for the anti-Markovnikov hydrosilation of olefins.2 Mechanistic studies on this catalysis were complicated by a lack of information concerning fundamental reaction steps that are possible for such 2-coordinate, high-spin metal centers. Thus, investigations focus on defining the fundamental transformations (e.g., redox events, bond activations) that are possible in such low-coordinate systems.
