What is "bisnickel"

Bis(cyclooctadiene)nickel(0) is the organometallic compound with the formula Ni(CH). This air-sensitive yellow solid is a common source of Ni(0) in chemical synthesis.

Ni(cod), as it is commonly abbreviated, is a diamagnetic coordination complex featuring tetrahedral nickel(0) bound to the alkene groups in two 1,5-cyclooctadiene ligands. The complex is prepared by reduction of anhydrous nickel(II) acetylacetonate in the presence of the diolefin:

1/3 [Ni(acac)] + 2 cod + 2 AlEt → Ni(cod) + 2 acacAlEt + CH + CH

Ni(cod) is moderately soluble in benzene and THF. The cod ligands are easily displaced by phosphines, phosphites, and isocyanides.