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{κ(2)-HN(CH2CH2PPh2)2}(CO)4]. The molybdenum analogue readily loses a carbonyl ligand to form [Mo{κ(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)2Ru{S2CN(CH2CH2PPh2)2}M(CO)4](+), while treatment with [ReCl(CO)5] yields [(dppm)2Ru{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.