Diiminepyridine Chemistry

The diiminepyridine ligand, first made world-famous by Brookhart and Gibson, is a curious one. Unlike most traditional ligands, it tends to participate actively in the chemistry of its complexes, be it through strong p-acidity, through uptake of one, two or even three discrete electrons from the metal(s) bound to it, or even through ligand-centered chemical reactivity. It is also unique in giving iron and cobalt complexes active in olefin polymerization. As yet, it is still not completely clear in how far these properties are related.

The ligand is typically terdentate, but its complexes are highly strained, and there are several examples of easy loss or exchange of the coordinated metal atom.

We are exploring the nature and selectivity of its ligand-centered reactivity, and trying to construct even more p-acidic analogs for use in catalysis. For relevant papers, see numbers 66, 77-79, 89, 90, 93, 94, 96, 97, 100, 101, 103, 105, 108, 113, 115, 117, 123, 126, 129, 131 of my publication list.