Heterobinuclear and heterotrinuclear metal mu-allenyl complexes containingplatinum and one or both of iron and ruthenium. Synthesis of higher nuclearity metal complexes from mononuclear metal eta(1)-propargyls and eta(1)-allenyls and from binuclear metal mu-eta(1):eta(2)alpha,beta-allenyls

The reactions of Cp(CO)(2)MCH2C=CPh with Pt(PPh3)(4) or Pt(PPh3)(2)C2H4 in THF at reflux and of Cp(CO)(2)MCH=C=CH2 with Pt(PPh3)(2)C2H4 in THF or hexa ne at -78 degrees C to ambient temperature afforded the heterobinuclear met al mu-allenyl complexes (PPh3)(2)Pt(mu-mu(1):eta(alpha,beta)(2)-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 Ru-3(CO)(12) or Fe-2(CO)(9) (Ru , Fe = M') in THF at room temperature to yield open heterotrinuclear metal mu-allenyl complexes (PPh3)-(CO)Pt(mu(3)-eta(l):eta(2):eta(2)-C(R)=C=CH2)M' (CO)(3)M( CO)Cp (M' = M = Ru, R = H (4); M' = Ru, M = Fe, R = H (5); M' = F e, M = Ru, R = Ph (6a); M' = Fe, M = Ru, R = H (6b); M' = M = Fe, R = H (7) ), as well as M'(CO)(4)PPh3. The reaction of 1a with Fe-2(CO)(9) also affor ded the CO for-PPh3 substitution product (PPh3)(CO)Pt(mu-eta(1):eta(alpha,b eta)(2)-C(Ph)=C=CH2)Ru(CO)Cp (3). Treatment of the mu-allenylcarbonyl (CO)( 3)Fe(mu-eta(3):eta(2)-C(O)C(Ph)=C=CH2)Ru(Co)Cp with Pt(PPh3)(2)C2H4 in THF at O "C with warming to ambient temperature gave three heterometallic produ cts: 6a, the PPh3-for-CO substituted (PPh3)(CO)(2)Fe(mu-eta(3):eta(2)-C(O)C (Ph)=C=CH2)Ru(CO)Cp, and (PPh3)(2)Pt(mu(3)-eta(1):eta(1):eta(3)-C(Ph)CCH2)R U(CO)Cp(mu(2)-CO)Fe(CO)(2) (8). All new products were characterized by a co mbination of IR and NMR (H-1, C-13{H-1}, and P-31{H-1}) spectroscopy, FAB m ass spectrometry, and elemental analysis; the structures of Ib, 3, 6a, and 8 were elucidated by X-ray diffraction analysis. Complexes Ib and 3 each co ntain a Pt-Ru bond and a mu-allenyl group that is eta(1) ligated to Pt and eta(2) ligated, through the internal C=C bond, to Ru. 6a contains an open P t-Fe-Ru metal framework, with the mu-C(Ph)=C=CH2 ligand being attached eta( 1) to Pt, eta(2) through the C(Ph)=C to Fe, and eta(2) through the C=CH2 to Ru. 8 is also an open, Pt-Fe-Ru bonded cluster; however, it contains an et a(3)-allyl group ligated to Fe and metalated at CPh (Ru) and C-beta (Pt). P ossible mechanisms of formation of the new mu-allenyl-metal complexes are p resented. Complexes 1 and 2 underwent fragmentation of the binuclear framew ork to yield Cp(CO)(2)MCH=C=CH2 (M = Ru, Fe), Cp(CO)(2)RuC(Ph)=C=CH2, or Cp -(CO)(2)FeCH2C=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 eta(1)- allenyl complexes, but not for Cp(CO)(2)FeCH2C=CPh.