Solid-supported continuous flow synthesis in microreactors using electroosmotic flow

This paper reports the fabrication of a microreactor suitable for use with supported reagents. We demonstrate that the electroosmotic flow can be used to move the reagents over a solid-supported catalyst bed. It is demonstrated that it is important that the support should not swell in organic solvents to obtain reproducible flow, and it is shown that silica supports fulfill this criteria. Silica-functionalised piperazine is used in a variety of Knoevenagel reactions to give the product in high conversion.