Synthesis and characterisation of diphenylvinylphosphine-substituted osmium and ruthenium carbonyl clusters; crystal and molecular structures of [Os3(CO)11(Ph2PCHCH2)] and [Os3(µ-H)(CO)9(µ-Ph2PCHCH)

Abstract

Reaction of the activated clusters [Os3(CO)12 –n(NCMe)n](n= 1 or 2) with diphenylvinylphosphine (Ph2PCHCH2) afforded [Os3(CO)12 –n(Ph2PCHCH2)n](n= 1 1 or 2 2) in good yield. Addition of Ph2PCHCH2 to [Os3(µ-H)2(CO)10] resulted in the formation of [Os3(µ-H)H(CO)10(Ph2PCHCH2)]3. The ruthenium clusters [Ru3(CO)12 –n(Ph2PCHCH2)n](n= 1 4 or 2 5) have been synthesised by the reaction of [Ru3(CO)12] with an excess of diphenylvinylphosphine in the presence of a catalytic amount of Na–Ph2CO. Thermolysis of 1 led to the formation of [Os3(µ-H)(CO)9(µ3-Ph2PCHCH)]6 in which the vinyl moiety has undergone β elimination. Similarly, 4 and 5 are converted into [Ru3(µ-H)(CO)9(µ3-Ph2PCHCH)]7 and the known complex [Ru3(µ-H)(CO)8(Ph2PCHCH2)(µ3-Ph2PCHCH)]8 under mild conditions (thermolysis or photolysis). No intermediate species could be detected during the formation of 6–8. All of the new clusters 2–7 have been fully characterised on the basis of their spectroscopic data and the molecular structures of 1 and 6 have been established by single-crystal X-ray analysis.