Design and Applications of Boranes and Boryls with Enhanced Acceptor Properties

• Applicant: Professor Dr. Marcel Schorpp
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2025
• Website: Homepage
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 572722242

The proposed project aims to develop novel boranes and boryls featuring strongly electron-withdrawing and/or sterically demanding substituents.A key objective of the project is the synthesis of the soft and hard Lewis superacid B(PyrF)₃ (PyrF = C6F4N), which holds the potential to surpass and potentially replace the commonly used Lewis acid B(C6F5)₃ in both stoichiometric and catalytic applications.The targeted asymmetrically substituted boranes are characterised by their high steric demand. This could enable Lewis acid catalysis, even in the presence of moisture, for example, in the reductive amination of carbonyl compounds. Furthermore, they provide novel opportunities for frustrated Lewis pair catalysis with sterically unprotected Lewis bases and substrates.Another key focus is the synthesis of borenium cations, with extraordinarily high, computationally predicted Lewis acidities. These compounds are anticipated to facilitate the binding, activation or functionalisation of chemically inert substrates, such as CO, CO₂, N₂, or C–C bonds.The second phase of the project focuses on novel boryl ligands. These X-type ligands exhibit strong σ-donor properties with unusually pronounced π-acceptor abilities for this class of ligand. Upon coordination to a central atom, they are expected to allow for the simultaneous tuning of donor and acceptor orbital energies, thereby enhancing reactivity in bond scission and transfer processes. Furthermore, the boryl provides a Lewis-acidic boron centre in close proximity to the central atom, which is anticipated to facilitate novel cooperative reactivities between boron and the central atom.

• DFG Programme: Research Grants