The reactions and coordination geometry of bis(2-pyridyl)amine (Hdpa) and its deprotonated anion (dpa) can be effectively modified by the reaction conditions. Depending on the solvent system, the reaction of multinuclear ruthenium carbonyls such as Ru3(CO)12 and [Ru(CO)3Cl2]2 with Hdpa at moderate reaction temperatures lead to low yields of a monomeric cis(CO), cis(Cl)-Ru(Hdpa)(CO)2Cl2 or a dimeric metal metalbonded [Ru(dpa)2(CO)2]2. In organic solvents high temperatures favor the formation of [Ru(dpa)2(CO)2]2 from clustered Ru3(CO)12 and Hdpa. The high-temperature reactions in HCl solution can, in turn, be used for selective synthesis of cis(CO),cis(Cl)-Ru(Hdpa)(CO)2Cl2. dpa (deprotonated with CH3Li) readily reacts with [Ru(CO)3Cl2]2, Ru3(CO)12, or H4Ru4(CO)12 in organic solvents, leading to [Ru(dpa)2(CO)2]2. Under the corresponding conditions Os carbonyls produce a new type of dpa-bridged dimer compound without a direct metalmetal bond, [Os(dpa)(CO)2(CH3)]2, in addition to the ruthenium dimer equivalent [Os(dpa)2(CO)2]2.