Nucleophilic Additions to Allenylidene Ruthenium Complexes

Allenylidene complexes [Ru­(η5-C9H7)­(CCCPh2)­{P­(OR)3}­(PPh3)]­[PF6] (R = Et (1), Me (2)) have been synthesized by the reaction of the complexes [Ru­(η5-C9H7)­Cl­{P­(OR)3}­(PPh3)] with 1,1-diphenyl-2-propyn-1-ol in the presence of NaPF6. Addition of different nucleophiles to complex 1 allows the synthesis of new allenyl or alkynyl ruthenium complexes depending on the regiochemistry of the reaction. Unexpected complexes [Ru­(η5-C9H7)­{κ3(C,C,C)-C­(R2PCH2CHCH2)CCPh2}­{P­(OEt)3}]­[PF6] (R = iPr (9a), Ph (9b)), containing an unusual κ3(C,C,C)-ligand have been obtained from the reaction of the allenylidene complex 1 with alkenylphosphane Ph2PCH2CHCH2 (ADPP) or iPr2PCH2CHCH2 (ADIP). The formation of these complexes is proposed to proceed through an intermediate, [Ru­(η5-C9H7)­(CCCPh2)­{P­(OR)3}­{κ1(P)-R2PCH2CHCH2}]­[PF6].