Cluster build-up in aqueous solution: synthesis, structure, protonation and catalytic properties of the trinuclear cation [(η6-C6H6)(η6-C6Me6)2Ru3(μ2-H)3(μ3-O)]+
The trinuclear ore-capped cluster cation [(eta(6)-C6H6)(eta(6)-C6Me6)(2)Ru-3(mu(2)-H)(3)(mu(3)-O)](+) (2) was synthesised by reacting [(eta(6)- C6Me6)Ru(H2O)(3)](2+) with [(eta(6)-C6Me6)(2)Ru-2(mu(2)-H)(3)](+) in aqueous solution. The single-crystal X-ray structure analysis of the tetrafluoroborate salt shows the cation to contain a H2O molecule hydrogen-bonded to the mu(3)-oxo ligand. Acidification experiments show two protonation steps occuring at this H2O molecule and the oxo cap of the triruthenium cluster. The cluster cation 2 catalyses the hydrogenation of aromatic compounds in aqueous solution under biphasic conditions. (C) 1999 Elsevier Science Ltd. All rights reserved.