A process for an improved oxirane hydroformylation catalyst, the improved oxirane hydroformylation catalyst, and a one step process for preparing a 1,3-diol in the presence of such a catalyst. One process for preparing the hydroformylation catalyst involves:a) forming a complex (A) by contacting a ruthenium(0) compound with a ditertiary phosphine ligand; and b) forming a complex (B) by subjecting complex (A) to a redox reaction with a cobalt(0) carbonyl compound.
