A team of chemists from VU Amsterdam, University of Oxford, and Okayama University has developed a powerful new method to construct small, ring-shaped carbon frameworks that are essential building blocks in medicines and widely used insecticides such as permethrin.
These compounds, known as alkylidenecyclopropanes, are challenging to synthesize —particularly when it comes to controlling their three-dimensional shape. This control is critical because mirror-image versions of the same molecule can exhibit very different biological properties. The new approach, published this week in Nature, overcomes these long-standing challenges, delivering products in a highly targeted and selective way.
Precision through catalysis
At the heart of the discovery is a newly developed catalyst that enables chemists to guide the reaction with remarkable control. By using readily available starting materials, the catalyst directs the assembly of the strained three-membered rings with exceptional selectivity, minimizing waste and maximizing yield. This advance opens a practical new route to molecules at the core of pharmaceuticals and insecticides.
Computation reveals the origin of selectivity
To understand why the reaction works so efficiently and selectively, the team combined experiments with state-of-the-art quantum chemical simulations that were led by Trevor A. Hamlin, Assistant Professor at VU, and assisted by PhD student Eveline Tiekink. Trevor explains: “Using density functional theory (DFT) calculations, we were able to map out the reaction pathway and pinpoint the key step that dictates selectivity. These insights revealed how the catalyst subtly biases the geometry of the reacting molecules, guiding them along one trajectory over another. This mechanistic understanding not only explains the success of this transformation but also provides a blueprint for designing the next generation of selective catalysts.”
Broader significance
Beyond its immediate application to the synthesis of permethrin and related compounds, this study highlights the value of integrating computational chemistry with experimental discovery. By showing how fundamental insights into reaction mechanisms can inform catalyst design, the research paves the way for new strategies to tackle some of the most challenging molecular transformations in chemistry.