Support Engineering for the Stabilisation of Heterogeneous Pd P-Based Catalysts for Heck Coupling Reactions.

Herein we report the use of a supported Pd P catalyst for Heck coupling reactions. For the stabilisation of Pd P and Pd, as reference system, the silica support material was modified via phosphorus doping (0.5 and 1 wt % P). Through this so-called support engineering approach, the catalytic activity of Pd P was clearly enhanced. Whereas an iodobenzene conversion of 79 % was witnessed for Pd P@SiO in the coupling of styrene and iodobenzene in 1 h, 90 % conversion could be achieved using Pd P@1P-SiO . This improved catalytic activity probably stems from an electronic modulation of the support surface via the introduction of phosphorus. Simultaneously, the recyclability was boosted and the Pd P@1P-SiO catalyst has shown to maintain its catalytic activity over several recovery tests. Hereby, metal leaching could almost be suppressed completely to 3 % by the use of a P-modified silica support.