2 research outputs found
Reactivity studies on a binuclear ruthenium(0) complex equipped with a bridging Îș2N,Ge-amidinatogermylene ligand
The amidinatogermylene-bridged diruthenium(0) complex [Ru2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(CO)7] (2; iPr2bzam = N,NâČ-bis(iso-propyl)benzamidinate; HMDS = N(SiMe3)2) reacted at room temperature with tBuNC and PMe3 to give [Ru2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(L)(CO)6] (L = tBuNC, 3; PMe3, 4), which contain the new ligand in an axial position on the Ru atom that is not attached to the amidinato fragment. At 70 °C, 2 reacted with PPh3, PMe3, dppm, and dppe to give the equatorially substituted derivatives [Ru2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(L)(CO)6] (L = PPh3, 5; PMe3, 6) and [Ru2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(ÎŒâÎș2P,PâČ-L2)(CO)5] (L2 = dppm, 7; dppe, 8). HSiEt3 and HSnPh3 were oxidatively added to complex 2 at 70 °C, leading to the coordinatively unsaturated products [Ru2(ER3)(ÎŒ-H){ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(CO)5] (ER3 = SiEt3, 9; SnPh3, 10), which easily reacted with tBuNC and CO to give the saturated derivatives [Ru2(ER3)(ÎŒ-H){ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(tBuNC)(CO)5] (ER3 = SiEt3, 11; SnPh3, 12) and [Ru2(ER3)(ÎŒ-H){ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}(CO)6] (ER3 = SiEt3, 13; SnPh3, 14), respectively. Compounds 9â14 have their ER3 group on the Ru atom that is not attached to the amidinato fragment. In contrast, the reaction of 2 with H2 at 70 °C led to the unsaturated tetranuclear complex [Ru4(ÎŒ-H)2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}2(CO)10] (15), which also reacted with tBuNC and CO to give the saturated derivatives [Ru4(ÎŒ-H)2{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}2(L)2(CO)10] (L = tBuNC, 16; CO, 17). All tetraruthenium complexes contain an unbridged metalâmetal connecting two germylene-bridged diruthenium units. Under CO atmosphere, complex 17 reverted to compound 2. All of the coordinatively unsaturated products (9, 10, and 15) have their unsaturation(s) located on the Ru atom(s) that is(are) attached to the amidinato fragment(s). In the absence of added reagents, the thermolysis of 2 in refluxing toluene led to [Ru4{ÎŒâÎș2Ge,N-Ge(iPr2bzam)(HMDS)}{ÎŒ3âÎșGe-Ge(HMDS)}(ÎŒâÎș3N,C,NâČ-iPr2bzam)(ÎŒ-CO)(CO)8] (18), which contains two new ligands, a triply bridging germylidyne and a bridging benzamidinate, and that results from the condensation of two molecules of 2 and the activation of the GeâN bond of the benzamidinatogermylene ligand of 2.This work has been supported by a European Union Marie Curie reintegration grant (No. FP7-2010-RG-268329), by Spanish MINECO-FEDER research projects (Nos.
CTQ2010-14933, RYC2012-10491, CTQ2013-40619-P, and MAT2013-40950-R), and by a research grant from the Government of Asturias (No. GRUPIN14-009).Peer Reviewe