Reactions of the pentanuclear mixed-metal cluster compound [Ru4RhC(CO)12(η5-C5Me5)]. Synthesis, characterisation and crystal structure of the pentanuclear derivative [Ru4RhC(CO)11H(η5-C5Me5)I]
Abstract
Treatment of the pentanuclear cluster [Ru4RhC(CO)12(η5-C5Me5)]1 with an excess of [NEt4][BH4] yielded the monoanion [Ru4RhC(CO)11H(η5-C5Me5)]– which has been isolated as its [NEt4]+ salt 2. Reaction of the monoanion with iodine solution gave the novel derivative [Ru4RhC(CO)11H(η5-C5Me5)I]3. Compound 3 crystallises in the monoclinic space group P21/n with a= 15.243(3), b= 18.683(3), c= 10.425(2)Å, β= 90.0(2)°. The five metal atoms adopt a wingtip-bridged butterfly arrangement with the rhodium forming one of the ‘hinge’ atoms [Ru–Ru 2.816(1)–2.899(1), Ru–Rh 2.816(1)–2.826(1)Å]. The parent cluster [Ru4RhC(CO)12(η5-C5Me5)]1 reacted at room temperature with the neutral ligands P(OMe)3 and PPh3 to yield compounds [Ru4RhC(CO)10{P(OMe)3}2(η5-C5Me5)]4(three isomers) and [Ru4RhC(CO)10(PPh3)2(η5-C5Me5)]5. Compound 1reacts with [N(PPh3)2]Cl to yield the adduct [Ru4RhC(CO)12(η5-C5Me5)Cl]– which on protonation produces [Ru4RhC(CO)12H(η5-C5Me5)Cl]6.