THE HIGHLY REACTIVE THIOLATE-BRIDGED DIRUTHENIUM COMPLEX [CP-ASTERISK-RU(MU(2)-CL)(MU(2)-SPRI)2RUCP-ASTERISK][OTF] - ITS REACTIONS WITH ALKYNES TO FORM DINUCLEAR METALLACYCLES AND TERMINAL ALLENYLIDENE COMPLEXES

Addition of AgOTf (OTf = OSO2CF3) to a THF solution of Cp*Ru(Cl)(mu2-SPr(i))2RU(Cl)CP* (1; CP*=eta5-C5Me5 produces [Cp*Ru(mu2-Cl)(mu2-SPr(i))2RUCp*][OTf] (2), which readily reacts with alkynes to form a new set of novel diruthenium complexes in high to excellent yield (Scheme 1). Reaction of 2 with HC=CC=CH(CH2)3CH2 (8 equiv) in THF at room temperature results in coupling of the two alkyne molecules at the diruthenium center to form the unique dinuclear metallacycle 3. Similar treatment of 2 with HC=CR (R = Tol, Ph) induces another type of almost quantitative coupling of the alkyne to afford diruthenacyclopentadienoindane complexes 4 (4a,R'=Me;4b,R'=H). Complex 2 also smoothly reacts with HC=CC(OH)R2 (R = Tol, Ph) to give dinuclear terminal allenylidene complexes 6 (6a, R = Tol; 6b, R = Ph). Complexes 3 and 6a have been defined by X-ray crystallography, whereas other compounds were spectroscopically characterized.