Heck coupling reaction catalyzed by [(C3H5)PdCl]2-N,N,N′,N′-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine

Pd-N,N,N′,N′-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine was used for Heck coupling reaction and showed a good activity. When the molar ratio of substrate to palladium was 1000, the yield of the coupling product was up to 99% for activated aryl bromides and 58% for aryl chloride. 31P NMR in situ indicated that the good activity of this system results from the active palladium species stabilized effectively by this tetraphosphine.

Graphical AbstractIn the presence of 0.1 mol% palladium–tetraphosphine complex, Heck coupling of arylchloride with styrene gives a yield of 58% and the reaction of arylchloride with ethyl acrylate gives a high yield of 96%.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights►An efficient methodology is developed for Heck coupling reaction in palladium–tetraphosphine system. ►Synthesis of the tetraphosphine is very convenient. ►The coupling of arylchloride with styrene gives a yield of 58% in 1000 molar ratio of substrate to catalyst at 120 °C. Similarly, a high yield of 96% is obtained with arylchloride and acrylate as the substrates. ►The structure information of active complex is indicated with NMR in situ.