(446c) Template Free Synthesis of Palladium Immobilized Ordered Mesoporous Resin for Drug Synthesis on a Chip

Packed bed microreactors are strong candidates for pharmaceutical applications to efficiently screen new catalyst and synthesize new drugs. In this project we synthesized a novel template-free ordered mesoporous resin (OMR) immobilized with palladium. The primary catalyst characterization showed high BET surface area (675.34 m2/g) and high thermal stability (TG more than 255 ºC) which made it a superior heterogeneous catalyst for cross-coupling reaction. The batch experiment results showed high conversion rate (98%) for Suzuki-Miyaura cross-coupling reaction up to 5 times of recyclability. A packed bed microreactor was developed to investigate the catalyst efficiency for cross-coupling reaction. The microreactor employs a U-shape channel which is filled with Pd-OMR catalyst. The reaction carried out across a range of liquid flow (0.1 t0 0.5 µl/min) rates, bed porosity percentage, and temperature (65 t0 85 ºC). Experiments seek to assign a reaction conversion and catalyst stability to each flow rate. The results show that the conversion in the continuous system is greater than the batch system, which is due to the mass transfer enhancement induced by the porosity of the catalyst. Reaction time within the microchannel is sufficiently small so that selectivity towards the product is nearly 100% across all flow regimes. In this work, we relate our map of conversion to the flow behavior and microreactor geometry, and we discuss steps for further exploring the mass transfer characteristics of the flow. This heterogeneous reactor architecture shows a promising pathway synthesize new drugs.