Polycrystalline samples of Pr- and Ti-substituted La2RuO5 were prepared applying a soft-chemistry route based on the thermal decomposition of citrate-stabilized precursors. The simultaneous substitution on the La-sites by Pr and on the Ru-sites by Ti results in samples of the composition La2-xPrxRu1-yTiyO5 with 0 <= x <= 0.75 and 0 <= y <= 0.4. The crystal structures of these compounds were analyzed by Rietveld refinement of powder X-ray diffraction patterns. For pure La2RuO5 a structural transition from a monoclinic room-temperature modification to a triclinic low-temperature structure was found at 161 K. This structural change is linked to a low-temperature long-range ordered spin-singlet ground state formed by Ru4+ spin-moments. Both the structural transition and the formation of the singlet ground state become progressively suppressed with higher Ti contents, while the Pr substitution has only a minor influence on the dimerization. The behavior of the Curie-Weiss temperatures can be explained assuming two almost independent magnetic sublattices corresponding to the ruthenium and the rare-earth ions, respectively. For all investigated properties, i.e. crystal structure, magnetic susceptibilities, and dimerization temperature T-d, a completely additive behavior of the effects of Pr-substitution and Ti-substitution is observed. (C) 2013 Elsevier Ltd. All rights reserved.