Challenging Ozonolysis

This proposal is aimed at delivering breakthrough technology for exploiting a number of potentially very valuable reactions that are rarely used in the pharmaceutical industry due to constraints posed by conventional laboratory hardware. The focus is on ozonolysis reactions which are characterised by minimal environmental impact and high efficiency. In spite of these attributes they have not found widespread applications due to safety concerns. Micro channel continuous flow reactors offer an excellent solution to these issues. This is due mainly to the small distances present for mass / heat transfer and quenching, and improved heat management. Ozonolysis is an example of multiphase reactions with fast kinetics and high exothermicity, which can not be performed currently in commercially available flow chemistry systems. In multiphase reactions, reactants from one phase have to pass through an interface, dissolve and then react in another phase. Transport phenomena play a crucial role in reaction performance. Thus, the behaviour of the reaction (which is the prime domain of the chemist) is inexorably linked with transport phenomena (which are the prime domain of the chemical engineer). For this reason, successful development of flow chemistry systems and protocols for multiphase reactions requires input from both disciplines.In this proposal we endeavour to develop novel, easy to use, intrinsically safe, continuous flow, microchannel reactor systems, via collaboration between two research teams with strong track records in organic synthesis and microreaction technology and two industrial partners with expertise in medicinal chemistry and flow chemistry instrumentation. Based on the chemistry of ozone as a hydride acceptor, we aim to identify and exploit completely new, greener, highly efficient and less laborious synthesis pathways that can be employed to manufacture high value compounds of relevance to the pharmaceutical industry from inexpensive raw materials.