Speaker:  Dr Manuel Nuño, Vapourtec Ltd, Suffolk, United Kingdom

Host:  Professor Richard Payne    [Map]

Terpenes, such as valencene, are low cost, natural products which can modified into more added value compounds such as nootkatone, following conventional chemical routes involving heavy metals, such as chromium.

Although electrochemistry was discovered more than two centuries ago, the limitations of batch electrochemistry have been restricting its use in organic synthesis. Vapourtec has recently developed the Ion Electrochemical Reactor, which takes advantage of the extremely large surface-to-volume ratios that a flow microreactor provides to make selective oxidation of terpenes. This is viable under mild chemical conditions using either air or oxygen as oxidant. By way of example this talk shows the optimisation undertaken in the oxidation of Valencene to Nootkatone.

Functionalisation of C-H bonds has been a topic of study since H. J. Fenton reported his findings in 1894. Since then, organic chemists have been using organocatalysis to functionalise C-H bonds. It often requires the need of prefunctionalised starting materials to carry such activation. In recent years, the development of photoinduced processes have witnessed great progress with regards to photocyclisations and photocatalysed C-H functionalisation reactions. The limiting factor on these reactions is usually the photon density that irradiates the reagents. With the use of the newly developed 150W UV LED, we report the effect of photon density on 2+2 photocyclisation reactions.

The final part of the talk will focus on solid-phase peptide synthesis in flow. Although SPPS is a well-established technique, the lack of live inline data can lead to several problems, such as an incomplete peptide and waste of reagents. By recording the volume change in a variable bed flow reactor and, combined with an inline UV detector, Vapourtec’s team was able to evaluate difficult couplings and develop optimised conditions.