Asymmetric olefin metathesis catalysts based on chiral extended N-heterocyclic carbenes with a bicyclic framework

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In summary, this project deals with the development of new chiral Grubbs-Hoveyda II catalysts based on chiral extended N-heterocyclic carbenes with a bicyclic framework. The carbene precursors can be prepared in a few steps from camphor and although only one chiral backbone in the carbenes is proposed, several modifications of these carbenes will be possible due to the introduction of different sidearms. The application of camphoric acid provides an easy route to six-membered ring carbenes with chiral information in the backbone. Some analogues of Grubbs-Hoveyda II catalysts with these carbenes have already proven to give asymmetric induction in the asymmetric ring opening cross metathesis. A major investigation of the new complexes will be in the asymmetric ring-rearrangement metathesis (ARRM). So far, most examples of RRM have been carried out with achiral catalysts. Via this tandem reaction complex structures could be directly available in enantioenriched form relevant for natural and non-natural products.