Challenging the metallocene dominance in actinide chemistry with a soft PNP pincer ligand: new uranium structures and reactivity patterns.

A soft embrace for U: Replacement of C(5)Me(5) by the soft PNP pincer ligand is a successful strategy to promote new reactivities and support new structures for the actinide series (see picture, py-O = pyridine-N-oxide). The specific electronic and steric properties of the PNP ligand enable access to previously unreported structures not available for the C(5)Me(5) ligand set and support not only low-valent uranium but also the high-valent uranium(VI) ion.