Sulfinate as cocatalyst 2 : Palladium catalyzed dimerization of butadiene with acyloins

Toluenesulfinate serves as a cocatalyst for the selective formation of α-hydroxy α-octa-2,7-dienyl ketones (2, the products of C-C bond formation) in the reaction of palladium catalyzed dimerization of 1,3-butadiene with acyloins, while the same reaction using triphenylphosphine, instead of toluenesulfinate, as a cocatalyst provides a mixture of 2 and 2-oxy octa-2′,7′-dienyl ethers (3, the products of C-O bond formation).