Monomeric and Dimeric Disulfide Complexes of Nickel(II)

Elemental sulfur reacts with a bulky bis(phosphine)nickel(0) complex to give a monomeric nickel(II) η2-disulfido complex, oxidation of which results in the elimination of sulfur with dimerization to give an η2,η2-disulfidodinickel(II) derivative in which the S−S bond can be reductively cleaved in a redox-reversible fashion.