Pillarquinone-Based Porous Polymer for a Highly-Efficient Heterogeneous Organometallic Catalysis

Pillar[5]quinone (PQ[5])-based porous polymer has been prepared by crosslinking and oxidating pillar[5]arene (PA[5]). Quinone was used as an unorthodox ligand to load palladium-catalyst with high loading ratio (up to 12.0 wt %). Catalyst was well dispersed on solid support in the form of Pd2+-specie. Pd-loaded PQ[5]-based heterogeneous catalyst was highly efficient for Suzuki-coupling reactions (22- to 1485-fold higher than Pd/C based on turnover frequency). It was superior compared to other existing heterogeneous catalysts for selective catalytic reaction. This heterogeneous catalyst had good thermo-stability, and could be reused and recycled.