Synthetic and structural studies on the transition-metal fullerene complexes (η2-C60)M[(η5-Ph2PC5H4)2Ru] and (η2-C60)M[(η5-Ph2PC5H4)2Co]+(PF6)- (M = Pd, Pt) and the related compound {[η5-Ph2P(O)C5H4]2Co}+(PF6)-

A toluene solution Of C-60 reacted with an equimolar quantity of M(dba)(2) (M = Pd, Pt; dba = dibenzylideneacetone) and (eta(5)-Ph2PC5H4)(2)Ru or with M(PPh3)(4) and (eta(5)-Ph2PC5H4)(2)Ru at room temperature to give the dinuclear transition-metal fullerene complexes (eta(2)-C-60)M [(eta(5)-Ph2PC5H4)(2)Ru] (1, M = Pd; 2, M = Pt), whereas the o-dichlorobenzene solution of C-60 reacted with an equimolar amount of M(dba)(2) and [(eta(5)-Ph2PC5H4)(2)Co](+)(PF6)(-) or with M(PPh3)(4) and [(eta(5)-Ph2PC5H4)(2)Co](+)(PF6)(-) under similar conditions to afford the dinuclear transition-metal fullerene complexes (eta(2)-C-60)M[(eta(5)-Ph2PC5H4)(2)Co](+)(PF6)(-) (3, M = Pd; 4, M = Pt). In addition, the related complex {[eta(5)-Ph2P(O)C5H4](2)Co}(+)(PF6)(-) (5) was prepared by oxidation of [(eta(5)-Ph-2-PC5H4)(2)Co](+)(PF6)(-) with an excess amount of aqueous peracetic acid in acetone at room temperature. While 1-4 are the first examples of neutral and cationic dinuclear M/Ru and M/Co (M = Pd, Pt) fullerene complexes, 5 is the first organocobalt Cp complex containing a phosphoryl substituent. All products 1-5 have been fully characterized by elemental analysis, spectroscopy, and X-ray crystal diffraction techniques and, for 1 and 2, by cyclic voltammetry.