Within our laboratory, the syntheses of several related tricyclic sesquiterpene natural products have been completed, and, in all cases, the synthetic route employed the Pauson-Khand reaction (PKR) to generate the complex tricyclic core of each target.To further extend our studies within this area, we embarked upon synthesis of the[5,6,6]-fused tricyclic natural product α-duprezianene. Two main synthetic strategies towards construction of this complex and challenging target molecule have been investigated, and are described within.The first of these strategies focussed on direct formation of the central [5,6,6]-fused skeleton structure in a rapid and efficient fashion through the PKR. Initial synthetic endeavour thus focussed on the generation of suitable enyne intermediates to allow investigation of this key PKR. Towards this aim, a series of novel routes were proposed and investigated, ultimately delivering the requisite enyne intermediates.Regrettably, PKR of these enynes was unsuccessful and an alternative approach towards the target molecule was thus required.The second strategy towards formation of α-duprezianene involved initial construction of the related natural target sesquithuriferone. Indeed, formation of this target would provide a formal route to not only α-duprezianene, but also to a series of related sesquiterpene products. Once again, the PKR was employed in attempts to generate the [5,6,5]-fused tricyclic core of this target. In this regard, following investigation of several potential synthetic pathways, a robust and high yielding route was developed providing a formal total synthesis of sesquithuriferone. Key to this strategy was an extremely efficient PKR which furnished the [5,6,5]-skeletal core of sesquithuriferone in rapid fashion.In establishing this route, the original target α-duprezianene was also accessed in a formal manner. The success of this work serves to further reinforce the utility of the PKR within organic synthesis.
|Date of Award||8 Dec 2016|
- University Of Strathclyde
|Sponsors||EPSRC (Engineering and Physical Sciences Research Council)|
|Supervisor||William Kerr (Supervisor) & Craig Jamieson (Supervisor)|