Transformation of the Bis(diphenylphosphino)methane Ligand on the Ru3(CO)9 Framework. Synthesis and Characterization of Ru3(CO)9(μ3-η3-P(C6H5)CH2P(C6H5)(C6H4)), Ru3(CO)9(μ-H)(μ3-η2-P(C6H5)CH2P(C6H5)2), and Ru3(CO)10(μ-η2-P(C6H5)CH2P(C6H5)(C6H4))

Article abstract of DOI:10.1021/ja00301a018

Several transformations of the dppm ligand on Ru3 clusters have been established (dppm=bis(diphenylphosphino)methane), starting from the parent complex Ru3(CO)10(μ-η²-dppm), 1.In compound 2, Ru3(CO)9(μ3-η³-P(C6H5)CH2P(C6H5)(C6H4)), the Ru3(CO)9 fragment is bridged by the six-electron tridentate phosphine ligand.In compound 3, Ru3(CO)9(μ-H)(μ3-η²-P(C6H5)CH2P(C6H5)2), the Ru3(CO)9H fragment is bridged in a bidentate manner by the five-electron phosphine donor.In compound 4, Ru3(CO)10(μ-η²-P(C6H5)CH2P(C6H5)(C6H4)), the Ru3(CO)10 fragment is bridged in a bidentate manner by the four-electron phosphine ligand.Thermolysis of 1 at 80 deg C in cyclohexane affords 2 in high yield.Thermolysis of 2 in the presence of H2 affords 3 in high yield.Compound 3 can also be produced directly from 1 at 90 deg C in toluene.When CO is bubbled through a solution of 2 in refluxing cyclohexane, compound 4 is produced in high yield.Compound 4 reacts with H2 under reflux in cyclohexane to yield compound 3.When compound 4 is refluxed in cyclohexane under N2, compound 2 results.The nature of compounds 2,3, and 4 has been established by spectroscopic means and by X-ray diffraction methods: crystal data, 2, momoclinic, C_2h⁵-P2₁/c, Z=4, a=10.689(7) Angstroem, b=11.936(7) Angstroem, c=23.281(18) Angstroem, β=90.18(8) deg (t=-85 deg C), final R(F²)=3.8percent, NO=7725, NV=381; 3, monoclinic, C_2h⁵-P2₁/n, Z=4, a=10.593(2) Angstroem, b=13.850(2) Angstroem, c=20.720(3) Angstroem, β=94.12(1) deg (t=-155 deg C), final R(F²)=3.5percent, NO=7037, NV=384; 4, monoclinic,C_2h⁵-P2₁/n, Z=4, a=12.022(1) Angstroem, b=15.266(1) Angstroem, c=17.225(2) Angstroem, β=105.56(1) deg (t=-155 deg C), final R(F²)=3.5percent, NO=6755, NV=400.