Aren- und cyclopentadienyl-halbsandwichkomplexe des rutheniums mit oximaten, carboxylaten, iminen und azavinylidenen als liganden

Abstract

The reaction of [C 6H 6Ru(P iPr 3)Cl 2] ( 1) with NaONCRR′ in the presence of KPF 6 leads to the formation of the oximatoruthenium(II) complexes [C 6H 6Ru(η 2-ONCRR′)(P iPr 3)]PF 6 ( 2– 5) in 70–90% yield. Compound 5 (R  Me, R′  tBu) reacts with HNCPh 2 via ligand exchange to give [C 6H 6Ru(NCPh 2)(P i Pr 3)]PF 6 ( 8). The azavinylidene complex 8 has also been prepared from the acetatoruthenium derivative [C 6H 6Ru(η 2-O 2 CCH 3)(P iPr 3)]PF 6 ( 6), which can be obtained either from 1, CH 3CO 2Na and KPF 6 or from treatment of 5 with an excess of CH 3CO 2H. The synthesis of the hexamethylbenzeneruthenium compounds [C 6Me 6Ru(NCR′ 2)PR 3)]PF 6 ( 12– 15) is achieved by the reaction of the hydrido(chloro)metal complexes [C 6Me 6RuH(PR 3)Cl] ( 10, 11) with oximes HONCR′ 2 and AgPF 6. Nucleophilic addition of H − and CH 3 − to the NC carbon atom of [C 6Me 6Ru(NCPh 2)(PMe 3)] + affords the uncharged imitido compounds [C 6Me 6Ru(NCXPh 2) (PMe 3)] ( 16, 17). The cyclopentadienylruthenium complex [C 5H 5Ru(NCPh 2)(PPh 3)] ( 23) is prepared from either one of the imino derivatives [C 5H 5Ru(NHCPh 2)(PPh 3) 2]BF 4·0.5CH 2Cl 2 ( 22) or [C 5H 5Ru(NHCPh 2)(PPh 3)(O 2CCH 3)] ( 25) on treatment with NaR (R  H, C 5H 5). Compound 25 reacts in toluene at room temperature by elimination of CH 3CO 2H to give the five-membered metallaheterocycle [C 5H 5 Ru{NHC (Ph)C 6H 4}(PPh 3)] ( 26) which is an isomer of 23. The X-ray structural analysis of 5 reveals the presence of a O, N-bound oximato ligand and a cis position of the C 6H 6(P iPr 3)Ru and tBu units at the NC double bond.