Cationic Trinuclear 48-Electron Ruthenium Carbonyl Cluster Complexes Containing No Hydride Ligands

Abstract

In previous papers, we reported that the carbonyl cluster compound [Ru3@-H)@3-ampy)(CO)g] (1; Hampy = 2-amino6-methylpyridine) reacts with diphenylacetylene to give the alkenyl-bridged derivative [Ru3@3-ampy)@,q1:q2-PhC=CHPh)(co)S] ( 2 ) ' ~ ~ and that complex 2 can be protonated with HBF4.OEt2 to give [Ru3@-H)@3-ampy)@,q1 :q2-PhC=CHPh)(CO)s][BF4] (3) (Scheme 1).2a The presence of the alkenyl and hydride ligands in complex 3 prompted us to study reactions which might induce the reductive elimination of cis-stilbene and that would lead to cationic cluster compounds containing no hydride ligands. Simple protonation of neutral carbonyl cluster complexes frequently leads to hydridic cationic derivative^.^,^ However, in contrast with the geat number of neutral and anionic carbonyl cluster compounds reported to date: very few nonhydridic cationic carbonyl clusters have been d e s ~ r i b e d . ~ ~ As far as we are aware, and with the exception of the 50-electron compound [ R U ~ @ P P ~ ~ ) ~ ( C O ) ~ ] + , ~ all of the other nonhydridic cationic carbonyl cluster complexes are either 47-electron