The tetrametallic Fe ketimide cluster, [Fe4(NCPh2)6], exhibits a thermally persistent S = 7 ground-state along with single molecule magnet behavior.

Reaction of NiCl2 in THF with 2 equiv of Li­(CPh3) at −25 °C results in formation of Ni­(η3-CPh3)2 (1) in moderate yield. Complex 1 was fully characterized, which included analysis by X-ray crystallography. In the solid state, 1 features an η3 binding mode of its trityl ligands, resulting in a structure that is reminiscent of the archetypal Ni­(II) organometallic, bis­(η3-allyl)­nickel. In addition, complex 1 has proved to be an excellent Ni(0) synthon. For example, reaction of 1 with excess CO resulted in formation of Ni­(CO)4 along with Gomberg’s dimer. Similarly, reaction of 1 with 4 equiv of PPh3 resulted in formation of Ni­(PPh3)4 (2). Presumably, its ability to function as a Ni(0) source is derived from the relatively high stability of the trityl radical, which results in weak Ni–C bonds that are susceptible to homolytic cleavage. Finally, reaction of 1 with 2 equiv of PPh3, in an attempt to form a larger Ni cluster, resulted in formation of [Ni3(μ3-PPh)­(μ-PPh2)2(PPh3)3] (3) in moderate yield. Its phosphide and phosphinidene ligands are derived from the formal reduction of the PPh3 ligand.