Abstract: | Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐ray Crystal Structures of Ru2(CO)3L(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (L = CO, PnBu3) Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 1 ) reacts with several phosphines (L) in refluxing toluene under substitution of one carbonyl ligand and yields the compounds Ru2(CO)3L(μ‐H)(μ‐PtBu2)(μ‐dppm)] (L = PnBu3, 2 a ; L = PCy2H, 2 b ; L = dppm‐P, 2 c ; dppm = Ph2PCH2PPh2). The reactivity of 1 as well as the activated complexes 2 a – c towards phenylethyne was studied. Thus 1 , 2 a and 2 b , respectively, react with PhC≡CH in refluxing toluene with elimination of dihydrogen to the acetylide‐bridged complexes Ru2(CO)4(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐dppm)] ( 3 ) and Ru2(CO)3L(μ‐η1 : η2‐C≡CPh)(μ‐PtBu2)(μ‐dppm)] ( 4 a and 4 b ). The molecular structures of 3 and 4 a were determined by crystal structure analyses. |