Electrospray mass spectrometry of [Ru 4( η6-C 6H 6) 4(OH) 4] 4+: first direct evidence for the persistence of the cubane unit in solution and its role as a precatalyst in the hydrogenation of benzene

Abstract

The electrospray ionisation mass spectrum of [Ru 4( η 6-C 6H 6) 4(OH) 4] 4+ shows that the main species present in aqueous solution are based on the intact cubane tetramer and the dimer [Ru 2( η 6-C 6H 6) 2(OH) 2] 2+. The latter species is an active benzene hydrogenation catalyst.