Bis(1-R-imidazol-2-yl)disulfides, (mim(R))(2) (R = Ph, Bu-l), and diselenides, (seim(Mes))(2), serve as bidentate N,N-donor ligands for main-group and transition metals. For example, [K (2)-(mim(Bul))(2)]MCl2 (M = Fe, Co, Ni, Zn), [K-2-(mim(Ph))(2)]MCl2 (M = Co, Zn), [K-2-(mim(Bul))(2)]CuX (X = Cl, l), and [K-2-(seim(Mes))(2)]MCl2 (M = Fe, Co, Ni) are obtained by treatment of (mim(Bul))(2) or (seim(Mes))(2) with the respective metal halide and have been structurally characterized by X-ray diffraction. On the other hand, the zerovalent nickel complex Ni(PMe3)(4) effects cleavage of the disulfide bond of (mim(Bul))(2) to give square-planar trans-Ni(PMe3)(2)( mim(Bul))(2) in which the (mim(Bul)) ligands coordinate via nitrogen rather than sulfur, a most uncommon coordination mode for this class of ligands. Although [K-2-(mim(R))(2)]MCl2 (M = Fe, Co, Ni, Zn) are not subject to homolytic cleavage of the S-S bond because the tetravalent state is not readily accessible, the observation that [K-2-(mim(Ph))(2)]CoCl2 and [K-2-(mim(Bul))(2)]CoCl2 form an equilibrium mixture with the asymmetric disulfide [K-2-(mim(Ph))(mim(Bul))]CoCl2 indicates that S-S bond cleavage via another mechanism is possible. Likewise, metathesis between disulfide and diselenide ligands is observed in the formation of [K-2-(mim(Bul)) (seim(Mes))]-CoCl2 upon treatment of [K-2-(mim(Bul))(2)]CoCl2 with [K-2-(seim(Mes))(2)]CoCl2.