SYNTHESIS AND DERIVATIVE CHEMISTRY OF [RU2(MU-PPH2)(MU-OH)2(ETA-6-P-CYMENE)2]+

The cationic diphenylphosphido-bridged compound [Ru2(mu-PPh2)(mu-OH)2(eta6-p-cymene)2][PF6] (2) has been prepared by reaction of the tri-mu-hydroxo complex [Ru2(mu-OH)3(eta6-p-cymene)2][PF6] (1) with diphenylphosphine. Complex 2 eliminates water on reaction with protic acids, incorporating the conjugate base of the added acid as a bridging ligand. Formic acid, acetic acid, phenol, and aniline react with 2 to give the monosubstituted compounds [Ru2(mu-PPh2)(mu-OH)(mu-L)(eta6-p-cymene)2][PF6] (L = HCO2, MeCO2, OPh, or NHPh), whereas methanol, thiophenol, 1,2-benzenedithiol, hydrochloric acid and isopropanol afford the disubstituted derivatives [Ru2(mu-PPh2)(mu-L)2 (eta6-p-cymene)2][PF6] (L = OMe, SPh, 1/2 S2C6H4, Cl, or H).