The total synthesis of illisimonin

• Applicant: Professor Dr. Markus Kalesse
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 502117743

The aim of this project is to complete the total synthesis of illisimonin, a new terpenoid with a highly oxygenated carbon skeleton. An additional challenge in this natural product is the trans-fused norbornane backbone. The aim of this project is to provide new concepts and methods for completing the synthesis of complex natural products and the synthesis of illisimonin with its above-mentioned challenges and new feature should be a show case of this endeavor. It is planned to complete the synthesis using a photochemical [2+2]-cycloaddition followed by a samarium-mediated 1,2-shift of the vinylic position. The trans-fused norbornane backbone should be constructed with the aid of a pinacol rearrangement. This step leads formally to an exchange of the bridges of the norbornane backbone. The end game of the synthesis should be the late-stage functionalization of a CH2-group under radical conditions. Alternatively, this goal can be achieved through a semi-pinacol rearrangement.

• DFG Programme: Research Grants