Synthesis, Structure, and Reactivity of Ruthenium(II) Terminal Imido Complexes
journal contributionposted on 18.03.1997, 00:00 by Anthony K. Burrell, Andrew J. Steedman
The reactions of [(η6-cymene)RuCl2]2 and [(η6-C6Me6)RuCl2]2 with LiNH−R (R = 2,6-diisopropylphenyl (Ar), 2,6-dimethylphenyl (Ar‘), 2,4,6-tri-tert-butylphenyl (Ar*)) lead to a number of different products depending on the nature of ligands employed. The addition of 2 equiv of LiNHAr to [(η6-C6Me6)RuCl2]2 gives the amido complex (η6-C6Me6)RuCl(NHAr). Reaction of 4 equiv of the lithium amides with the ruthenium complex [(η6-cymene)RuCl2]2 or [(η6-C6Me6)RuCl2]2 yields imido complexes. The steric bulk of the substituents on either the η6-arene or nitrogen influence the structure of the final product. Large ligands such as the η6-C6Me6 or the Ar* group prevent the formation of bridged complexes, while combinations of ligands which have smaller steric requirements give dimeric compounds. The structures of (η6-cymene)RuCl2(NH2Ar), (η6-C6Me6)RuCl(NHAr), and [(η6-cymene)Os(NAr)]2 are presented and discussed in relation to the previously reported structures of [(η6-cymene)Ru(NAr)]2 and (η6-cymene)Ru(⋮NAr*).