Phenyl–gold complexes of Ru6 and Ru5 carbonyl clusters

Abstract

The reactions of Ru6(C)(CO)17, 1 and Ru5(C)(CO)15, 2 with (NHC)AuPh, NHC = 1,3-bis(2,6-diisopropylphenyl-imidazol-2-ylidene) have yielded the π-arene Ru6 complex Ru6C(CO)14[η6-PhAu(NHC)], 3 and two Ru5 complexes, Ru5C(CO)14(Ph)[μ-Au(NHC)], 4 and Ru5C(CO)13(μ–η2-Ph)[μ-Au(NHC)], 5, respectively. Compounds 4 and 5 were formed by oxidative-addition of the Au–C bond at the ruthenium atoms. Compound 5 contains a μ–η2–σ–π-coordinated phenyl ligand that is dynamically interchanging its coordination between the two sides of the ring on the 1H NMR time scale at room temperature. Compounds 4 and 5 both react with CO to yield the CO insertion product Ru5C(CO)14(μ–η2-OCPh)[μ-Au(NHC)], 6 that contains a bridging benzoyl ligand in an opened Ru5 cluster complex. The syntheses and X-ray crystal structures of these new complexes are reported.