Insertion reactions of GaCp*, InCp* and In[C(SiMe3)3] into the Ru-Cl bonds of [(p-cymene)RuIICl2]2 and [Cp*RuIICl]4

The first carbonyl free ruthenium/low valent Group 13 organyl complexes are presented, obtained by insertion of ER (ER = GaCp*, InCp*, In[C(SiMe3)(3)]) into the Ru - Cl bonds of [(p-cymene) RuCl2](2), [Cp* RuCl](4) and [Cp* RuCl2](2). The compound [(p-cymene) RuCl2](2) reacts with GaCp*, giving a variety of isolated products depending on the reaction conditions. The Ru-Ru dimers [{(p-cymene) Ru}(2)(GaCp*)(4)(mu(3)-Cl)(2)] ( 1) and the intermediate [{(p-cymene) Ru}(2)(mu-Cl)(2)] (2) were isolated, as well as monomeric complexes [( p-cymene) Ru(GaCp*)(3)Cl-2] ( 3), [(p-cymene) Ru(GaCp*)(2)GaCl3] (4) and [(p-cymene) Ru(GaCp*)(2)Cl-2(DMSO)] ( 5). The reaction of [Cp* RuCl](4) with ER gives "piano- stool" complexes of the type [Cp* Ru(ER)(3)Cl] (ER = InCp* (6), In[C(SiMe3)(3)] ( 7), GaCp* ( 8)). The chloride ligand in complex 8 can be removed by NaBPh4, yielding [Cp* Ru(GaCp*)(3)](+)[BPh4](-) ( 9). The reaction of [ Cp* RuCl2] 2 with GaCp* however, does not lead to an insertion product, but to the ionic Ru(II) complex [Cp* Ru(GaCp*)(3)](+)[Cp* GaCl3](-) ( 10). The ER ligands in complexes 3, 5, 6, 7 and 8 are equivalent on the NMR timescale in solution due to a chloride exchange between the three Group 13 atoms even at low temperatures. The solid state structures, however, exhibit a different structural pattern. The chloride ligands exhibit two coordination modes: either terminal or bridging. The new compounds are fully characterized including single crystal X-ray diffraction. These results point out the different reactivities of the two precursors and the nature of the neutral p-cymene and the anionic Cp* ligand when bonding to a Ru( II) centre.