Segmented Tube Reactors (STR): A Simple Tool To Screen Multiple Reactions in Parallel in Batch Mode within a Single Tube

A simple tool to perform multiple reactions in parallel in batch mode in static segments within a single tube is described. The Segmented Tube Reactor (STR) involves using syringe pumps to load a section of Teflon tubing with solutions of reaction components while forming a preprogrammed gradient of one of the components (e.g., equivalents, concentration) along its length. Simultaneously, a chemically inert spacer is loaded to break the gradient into discrete static segments. Ten or more distinct sets of conditions can be quickly set up in a single experiment. Although the STR is set up in flow mode, reactions occur in batch mode within the tubes, usually by heating the STR for a desired duration. Segments are then individually sampled and analyzed to identify the conditions that provide the best performance. The technology is translatable: the STR was employed to screen for preferred reaction stoichiometries that were then duplicated on larger scale in batch mode in traditional lab equipment.