A Strange Nickel(I)−Nickel(0) Binuclear Complex and Its Unexpected Ethylene Oligomerization

The unusual heterovalent bimetallic NiI−Ni0 complex
{[η-C5H4CHN(C6F5)]Fe[η-C5H4PPh2]}2Ni2(Cl) (2) was isolated from the reaction between [η-C5H4CHN(C6F5)]Fe[η-C5H4PPh2] (1) and Ni(COD)2 in the presence of AlEtCl2 or
AlCl3. Complex 2 has been crystallographically characterized
and theoretically analyzed; it is catalytically active (TOF
90 500) and selective (91%) toward the formation of C4
oligomers from ethylene (300 psi) at 30 °C, the only other
significant isomer formed being C6.