Multifunctional biomass based chemicals for the offshore production and the influence of carbamate groups on the β-selectivity in rhamnosylations

Asger Munk Koue

Publikation: Bog/antologi/afhandling/rapportPh.d.-afhandlingForskning

Abstract

This Ph.D. thesis consists of four chapters. The first three chapters is centred around work on synthesizing new “green” production chemicals for the offshore industry. It is necessary to develop green alternatives to the currently used production chemicals to keep up with the green transition. By using readily available biomass molecules as the flexible core of the new production chemicals in a few synthetic steps, it opens up the possibility of introducing multiple functionalities to the production chemicals (Scheme 1).

Chapter 1 deals with the first attempt to synthesize a new type of H2S scavengers. These were based on functionalizing biomass molecules with aliphatic nitrile groups as the H2S scavenging groups. Chapter 2 continues the work of attempting to synthesize new H2S scavengers from biomass molecules. A series of thia-Michael acceptors was tested as the H2S scavenging group alongside formaldehyde functionalized derivatives of urea. Chapter 3 describes an investigation of the H2S scavengers from the two previous chapters, and whether they could function as corrosion inhibitors, which is another type of production chemical. The intention was to test the idea of multifunctionality in these new production chemicals.

The last of the four chapters in this thesis concerns a separate project in the field of β-selectivity in L-rhamnosylations. Controlling the configuration of the anomeric carbon is of major importance for the biological activity of oligosaccharides. The β-selectivity in L-rhamnosylations remains a challenging type of reaction to this day. In this work it was found that placing simple O-carbamate protective groups on the 4-hydroxyl group entailed an increase in the β-selectivity in L- rhamnosylations compared to the other hydroxyl groups or when there is not a carbamate group (Scheme 2).
OriginalsprogEngelsk
ForlagDepartment of Chemistry, Faculty of Science, University of Copenhagen
Antal sider188
StatusUdgivet - 2024

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