Exploring the configurational space of homogeneous catalysts

Abstract

Transition metal complexes are important in homogeneous catalysis reactions, especially in asymmetric hydrogenation reactions. The coordinated ligands in the complexes provide stability and selectivity. With the right combination of ligands and metal centre a high selectivity can be reached. To find optimal metal-ligand combinations, the chemical space is explored with high throughput computational methods. In these methods descriptors are obtained, usually from a single structure with one specific ligand configuration, which might not represent reality very well. In earlier research the chemical space of iridium(III), ruthenium(II) and manganese(I) complexes has been explored. And in this research additional analysis was done to look at possible relations between ligand configurations and descriptors. This was done by using three unsupervised dimensionality reduction methods, i.e. PCA, t-SNE and UMAP. PCA showed that the ligand configuration could have an influence on mainly electronic descriptors, but failed to show clusters in terms of relative stability. t-SNE and UMAP showed some clusters for the stability, as well as overlapping between certain ligand configurations. However, no definitive relations have been found, thus optimising the analysis methods and performing other statistical analysis on the descriptors might give different outcomes.