Macroporous monolith supports for continuous flow capillary microreactors

Abstract

A solid macroporous monolith is shown to be a suitable substrate for anchoring a palladium complex to obtain a continuous porous material suitable for conducting flow-through catalysis in capillary microreactors. The monolith for this study was GMA-co-EDMA [poly(glycidyl methacrylate-co-ethylene dimethacrylate)] in fused silica capillaries (250 micrometre internal diameter). Immobilisation of ligand was achieved by passing a solution of 5-hydroxy-1,10-phenanthroline, and palladium(II) was added. Suzuki-Miyaura catalysis was studied. The excellent flow-through properties, firm attachment to capillary walls, and robustness of the capillary systems for catalysis demonstrated after continuous reaction for four days indicate that this approach is suitable for further development of capillary-based microreactors that are suitable for continuous flow processes and parallel synthesis.