Catalysis is today exploited for preparing ca. 90% of chemical and pharmaceutical products. Use of catalysts allows for efficient chemical transformations, limiting the energy consumption and improving selectivity and atom economy. However, a large number of catalytic systems rely on noble metals (e.g. Pd, Pt, Rh, Ir, Au), with associated sustainability and toxicity issues. Indeed, all these metals are undergoing strong price fluctuations and will face supply limitations in the future. Moreover, given the toxicity of most precious metals, the tolerated thresholds in fine chemicals and active pharmaceutical ingredients are very low, which leads to high purification costs (solvents, energy, generation of waste). For these reasons, replacement of noble metals with the cheaper and generally less toxic 1st row transition metals – such as Mn, Fe, Co, Ni, Cu – is becoming a compelling goal for chemists, as well as a need for society. However, this goal also represents a tremendous challenge, as the typical reactivity of 2nd and 3rd row transition metals cannot be easily transferred to 1st row transition metals, due to their different electronic structure: the so-called "base metals" tend to form high-spin complexes and to engage in single electron transfer rather than in the multielectron redox steps typical of noble metals.
NextBase is an intersectoral consortium of research groups with a strong expertise in catalysis, who join forces to take the challenge of noble metal replacement in cross-coupling reactions – a class of transformations of high industrial importance to produce fine chemicals and active pharmaceutical ingredients. Synergies and complementary types of expertise within the Doctoral Network are exploited (i) to harness the reactivity of 1st row transition metals for several types of cross-coupling, which will be also applied to industrially relevant targets, and (ii) to train outstanding PhD students aware of the importance of sustainability issues and expert in the use and combination of different catalytic methodologies.
