Reactivity of the binuclear ruthenium ‘Pincer’ complex [{RuCl2(η3-NN′N)}2(μ-N2)] towards N-donor ligands. The X-ray crystal structure of [RuCl2(η3-NN′N)(NCPh)] (NN′N=2,6-bis[(dimethylamino)methyl]pyridine)

Treatment of the binuclear, dinitrogen-bridged complex [{RuCl2(η3-NN′N)}2(μ-N2)] (3, NN′N=2,6-bis[(dimethylamino)methyl]pyridine) with two equivalents of acetonitrile gives the mononuclear derivative mer,trans-[RuCl2(η3-NN′N)(NCMe)] (4), while the use of an excess of this ligand leads to the formation of the monocationic isomers mer,trans-[RuCl(η3-NN′N)(NCMe)2]Cl (5) and mer,cis-[RuCl(η3-NN′N)(NCMe)2]Cl (6). In contrast, when 3 is treated with an excess of benzonitrile or pyridine, the only products formed are mer,trans-[RuCl2(η3-NN′N)(NCPh)] (7) and mer,trans-[RuCl2(η3-NN′N)(py)] (8; py=pyridine), respectively. The X-ray structures of 7 and related reactions with other N-donor ligands are reported.