The complex [Ru(p-cymene)(dppe)Cl]PF₆·C₇H₈ has been synthesized and structurally characterized. It crystallizes in the orthorhombic non-centrosymmetric space group P2₁2₁2₁ and undergoes auto-resolution. The complex is an efficient catalyst for direct carbon–carbon bond-formation reactions using cinnamyl alcohols to produce enantio- and regioselective mono-allylation products of diketones in high yield. A wide range of substrates provides good to excellent yields. The use of pyrrolidine and acetic acid additives increases the selectivity as well as prevents unwanted side products.