Reaction of dithiols with Ni(dppe)Cl 2 gave monomeric or dimeric dithiolato compounds depending on the nature of the dithiol. Toluenedithiol (TDT) and 1,2-benzenedithiol (1,2-BDT) gave Ni(dope) (TDT) (1) and Ni(dppe) (1,2-BDT) (2), respectively, whereas 1,3-benzenedithiol (1,3-BDT) gave [Ni(dppe)Cl] 2 (1,3-BDT) (3). Single crystal X-ray diffraction studies of 2 showed a square planar nickel environment. Complexes 1 and 2 reacted rapidly and reversibly with SO 2 to form 1*dSO 2 and 2*dSO 2 , respectively. The reversibility of the SO 2 reactions was established by a combination of UV-Vis and 1 H NMR spectroscopy.