289685-71-8Relevant academic research and scientific papers
Heterobinuclear and heterotrinuclear metal μ-allenyl complexes containing platinum and one or both of iron and ruthenium. Synthesis of higher nuclearity metal complexes from mononuclear metal η1-propargyls and η1-allenyls and from binuclear metal μ-η1:η2α,β-allenyls
Willis, Richard R.,Shuchart, Chris E.,Wojcicki, Andrew,Rheingold, Arnold L.,Haggerty, Brian S.
, p. 3179 - 3191 (2008/10/08)
The reactions of Cp(CO)2MCH2C≡CPh with Pt(PPh3)4 or Pt(PPh3)2C2H4 in THF at reflux and of Cp(CO)2MCH=C=CH2 with Pt(PPh3)2C2H4 in THF or hexane at -78 °C to ambient temperature afforded the heterobinuclear metal μ-allenyl complexes (PPh3)2Pt(μ-η1:η2 α,β-C(Ph)=C=CH2)M(CO)Cp (M = Ru, R = Ph (1a); M = Fe, R = Ph (2a); M = Ru, R = H (1b); M = Fe, R = H (2b)). The products reacted with Ru3(CO)12 or Fe2(CO)9 (Ru, Fe = M′) in THF at room temperature to yield open heterotrinuclear metal μ-allenyl complexes (PPh3)-(CO)Pt(μ3-η1:η 2:η2-C(R)=C=CH2)M′(CO) 3M(CO)Cp (M′ = M = Ru, R = H (4); M′ - Ru, M = Fe, R = H (5); M′ = Fe, M = Ru, R = Ph (6a); M′ = Fe, M = Ru, R = H (6b); M′ = M = Fe, R = H (7)), as well as M′(CO)4PPh3. The reaction of 1a with Fe2(CO)9 also afforded the CO-for-PPh3 substitution product (PPh3)(CO)Pt(μ-η1:η2 α,β-C(Ph)=C=CH2)Ru(CO)Cp (3). Treatment of the μ-allenylcarbonyl (CO)3Fe(μ-η1:η3-η 2-C(O)C(Ph)=C=CH2)Ru(CO)Cp with Pt(PPh3)2C2H4 in THF at 0 °C with warming to ambient temperature gave three heterometallic products: 6a, the PPh3-for-CO substituted (PPh3)(CO)2Fe(μ-η3:η 2-C(O)C(Ph)=C=CH2)Ru(CO)Cp, and (PPh3)2Pt(μ3-η1:η 1:η3-C(Ph)CCH2)Ru(CO)Cp(μ 2-CO)Fe(CO)2 (8). All new products were characterized by a combination of IR and NMR (1H, 13C{1H}, and 31P{1H}) spectroscopy, FAB mass spectrometry, and elemental analysis; the structures of 1b, 3, 6a, and 8 were elucidated by X-ray diffraction analysis. Complexes 1b and 3 each contain a Pt-Ru bond and a μ-allenyl group that is η1 ligated to Pt and η2 ligated, through the internal C=C bond, to Ru. 6a contains an open Pt-Fe-Ru metal framework, with the μ-C(Ph)=C=CH2 ligand being attached η1 to Pt, η2 through the C(Ph)=C to Fe, and η2 through the C=CH2 to Ru. 8 is also an open, Pt-Fe-Ru bonded cluster; however, it contains an η3-allyl group ligated to Fe and metalated at CPh (Ru) and Cβ (Pt). Possible mechanisms of formation of the new μ-allenylmetal complexes are presented. Complexes 1 and 2 underwent fragmentation of the binuclear framework to yield Cp(CO)2MCH=C=CH2 (M = Ru, Fe), Cp(CO)2RuC(Ph)=C=CH2, or Cp-(CO)2FeCH2C≡CPh, as appropriate, in addition to Pt(PPh3)2(CO)2, upon treatment with CO at room temperature. The reverse of these processes can be effected by sweeping the product solutions with Ar for the three η1-allenyl complexes, but not for Cp(CO)2FeCH2C=CPh.
