Chloropalladated Propargyl Amine:  A Highly Efficient Phosphine-Free Catalyst Precursor for the Heck Reaction

The palladacycle {Pd[k¹-C, k¹-N-C(C₆H₅)C(Cl)CH₂NMe₂](μ-Cl)}₂ 1 derived from the chloropalladation of 3-(dimethylamino)-1-phenyl-1-propyne promotes the arylation of olefins under relatively mild reaction conditions. The coupling of iodoarenes and activated bromoarenes with n-butylacrylate and styrene occurs at room temperature. Turnover numbers of up to 85 000 have been achieved with deactivated bromoarenes and up to 1000 for activated chloroarenes at higher temperatures (80−150 °C).