Lejon, Tore

Projects

1. Synthesis of small focused libraries of barbituric acid containing compounds.

Barbituric acid was synthesized for the first time in the 19:th century and at the beginning of the 20:th century the first barbiturates with central nervous system activity were synthesized. The project is aimed at synthesizing derivatives of barbituric acid and will involve a number of different organic synthetic reactions.

            http://en.wikipedia.org/wiki/Barbiturate

2. Reductions

There are a number of different methods for reducing organic compounds and often these methods are specific/selective. In our laboratories potassium graphite has been used as reducing agent for a number of different reactions. The project is aimed at exploring the use of metal intercalates as reducing agents and is more focused on methodology than on synthesis of new compounds.

Examples of reductions can be found in any undergraduate level textbook.

3. SET

Single electron transfer reactions have found widespread use in organic chemistry. However, compounds such as tin hydrides are toxic and the development of new, less toxic, methods would add to the toolbox used by organic chemists. Methodological aspects will be focused on but there are also specific synthetic challenges needing good and reliable SET reagents.

http://en.wikipedia.org/wiki/Single_electron_transfer

4. Chromium carbenes

Carbenes are usually very reactive species that are difficult to handle and that react indiscriminately. By employing transition metals to stabilize these very reactive species carbenes have found widespread use in organic synthesis. There are reports on highly reduced chromium carbenes and this project is focused on the synthesis and use of these types of compounds.

http://en.wikipedia.org/wiki/Transition_metal_carbene_complex

5. Coupling reactions

The formation of carbon-carbon bonds is probably the most important reaction in organic chemistry. In this respect there is a multitude of reactions being employed, ranging from simple reactions introduced at the introductory level courses to highly sophisticated methods employing transition metal catalysis. Reactions to be investigated will be based on transition metal catalysis.

Examples of couplings can be found in any undergraduate level textbook.

6. Synthesis of natural products from fungi

Compounds found throughout nature are often the basis for lead compounds used in therapeutics. Some compounds found in fungi are highly toxic but there are also compounds with benign effect, e.g. anti cancer activity. A protocol is to be developed for synthesizing compounds with desired therapeutic activity.

Literature on the biochemistry of fungi is too vast to be covered here.

7. Synthesis of non-natural amino acids and peptidomimetics

Peptides consisting of naturally occurring amino acids are prone to enzymatic degradation. One common approach to overcoming this effect is to incorporate amino acids that are not found in nature in the peptides. Currently b-amino acids are synthesized with 1-4 substituents being introduced in enantioselective reactions, but there is still need for new compounds to be synthesized.

http://en.wikipedia.org/wiki/Peptidomimetic

8. Ultrasound promoted Wittig reactions

The use of ultrasound as a means for accelerating chemical reactions is known as sonochemistry and has been around for a long time. In addition to the rate increase there is evidence that the equilibrium of a chemical reaction can be changed by applying ultrasound. By combining the effect on rate and equilibrium it is possible to optimize reactions that are otherwise sluggish. The project aims at developing methodology for new applications of ultrasound in organic synthesis.

http://en.wikipedia.org/wiki/Sonochemistry