Palladium carboxylate/boron trifluoride etherate catalyst system for the selective dimerization of styrene

The selective dimerization of styrene to 1,3-diphenyl-1-butene with Pd(carboxylate)2 + BF3OEt2 catalyst system in both “phosphine-free” and “phosphine-modified” fashions has been investigated. For the Pd(OAc)2 + 2PR3 + 7BF3OEt2 catalyst system, a TON of 145 000 and 90% selectivity to dimers have been achieved at 80 °C for 5 h. This TON is twice as large as compared to that achieved with the Pd(β-diketonate)2-based systems. Styrene dimers up to 95% consist of trans-1,3-diphenyl-1-butene. The simplicity of this catalyst system composition might be of industrial importance.