The HCl salt of the aminodiphosphine ligand HN(CH2CH2PPh2)(2) reacts with [M(CO)(4)(pip)(2)] (M = Mo, W; pip = piperidine) to yield [M{kappa(2)-HN(CH2CH2PPh2)(2)}(CO)(4)]. The molybdenum analogue readily loses a carbonyl ligand to form [Mo{kappa(3)-HN(CH2CH2PPh2)(2)}(CO)(3)], which was structurally characterized. The same ligand backbone is used to form the new bifunctional ligand, KS2CN(CH2CH2PPh2)(2), which reacts with nickel and cobalt precursors to yield [Ni{S2CN(CH2CH2PPh2)(2)}(2)] and [Co{S2CN(CH2CH2PPh2)(2)}(3)]. Addition of [AuCl(tht)] (tht = tetrahydrothiophene) to [Ni{S2CN(CH2CH2PPh2)(2)}(2)] leads to formation of the pentametallic complex, [Ni{S2CN(CH2CH2PPh2AuCl)(2)}(2)]. In contrast, addition of [PdCl2(py)(2)] (py = pyridine) to [Ni{S2CN(CH2CH2PPh2)(2)}(2)] does not lead to a trimetallic complex but instead yields the transmetalated cyclic compound [Pd{S2CN(CH2CH2PPh2)(2)}](2), which was structurally characterized. The same product is obtained directly from [PdCl2(py)(2)] and KS2CN(CH2CH2PPh2)(2). In contrast, the same reaction with [PtCl2(NCPh)(2)] yields the oligomer, [Pt{S2CN(CH2CH2PPh2)(2)}]n. Reaction of KS2CN(CH2CH2PPh2)(2) with cis-[RuCl2(dppm)(2)] provides [Ru{S2CN(CH2CH2PPh2)(2)}(dppm)(2)](+), which reacts with [AuCl(tht)] to yield [Ru{S2CN(CH2CH2PPh2AuCl)(2)}(dppm)(2)](+). Addition of [M(CO)(4)(pip)(2)] (M = Mo, W) to the same precursor leads to formation of the bimetallic compounds [(dppm)(2)Ru{S2CN(CH2CH2PPh2)(2)}M(CO)(4)](+), while treatment with [ReCl(CO)(5)] yields [(dppm)(2)Ru{S2CN(CH2CH2PPh2)(2)}ReCl(CO)(3)](+). Reaction of KS2CN(CH2CH2PPh2)(2) with [Os(CH-CHC6H4Me-(4))Cl(CO)(BTD)(PPh3)(2)] (BTD = 2,1,3-benzothiadiazole) provides [Os(CH-CHC6H4Me-(4)){S2CN(CH2CH2PPh2)(2)}(CO)(PPh3)(2)], but reaction with the analogous ruthenium precursor fails to yield a clean product.