The ruthenium-catalysed hydrosilylation of CO2 was studied with respect to the influences of the solvent present and different co-ligands used. Nitriles exhibit favourable properties as a solvent for this reaction. The catalytic activity of [RuCl(MeCN)(5)]+[(trans)-RuCl4(MeCN)(2)](-) as pre-catalyst may be increased by additional phosphine ligand. Further N-donor substituents in the phosphine do not result in an increased activity. The homogeneous catalyst may be recycled effectively by a thermal separation of the reaction product. For this procedure, the catalytic activity kept constant during 10 runs. (C) 2004 Elsevier B.V. All rights reserved.