Carboranyl-Substituted Group 14 and 15 Elements: Lewis Acids, Z-Type Ligands and Ligand Redox-Non-Innocence Enabled Electromerism

• Applicant: Professor Dr. Lutz Greb
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560490200

Group 14 and 15 element compounds have recently garnered significant attention due to their unique and selective reactivity with inert bonds and small molecules. While much of this progress relied on the design of the ligands around these elements, the strategic application of carboranyl ligands is little explored. However, due to its peculiar electronic features, this ligand class offers numerous beneficial effects to enhance the reactivity and properties of these elements for novel directions in main group mediated bond activation and catalysis. In this work, we will synthesize a series of high-oxidation-state Si(IV), Ge(IV), and Sn(IV) compounds, along with P(III), P(V), Sb(III), and Sb(V) compounds, using carboranyl ligands. Our research will focus on three interconnected aspects: 1. Synthesis and Reactivity of New Carborane-Substituted Lewis Superacids: We aim to explore how carboranyl ligands affect the Lewis acidity of group 14 and 15 centers, with the goal of developing superacids. 2. Z-type Ligand Behavior in Transition Metal Chemistry: These Lewis acids will be investigated as Z-type ligands with transition metal centers, primarily Pd. We will study the reactivity between the element (E) and the transition metal (TM) during bond activation, aiming to discover new states and enrich applications in transition metal catalysis. 3. Redox Chemistry of the Carboranyl Ligands: We will explore how the redox chemistry of the carboranyl ligands influences the oxidation states and reactivity of group 14 and 15 centers. By toggling between low- and high-valent states, this approach will open new avenues for p-block element-based redox pathways and expand their role in catalysis and bond activation. In conclusion, this work aims to deepen our understanding of group 14 and 15 elements regarding their Lewis acidity and redox activity, while their role as Z-type ligands with transition metals may unlock new catalytic applications. The findings are expected to advance both catalysis and bond activation involving these elements.

• DFG Programme: Research Grants
• International Connection: Israel
• Partner Organisation: The Israel Science Foundation
• Cooperation Partner: Professor Dr. Roman Dobrovetsky