New iminophosphanes and iminoarsanes: Synthesis, properties and reactivity

• Applicant: Dr. Alexander Hinz
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 570065382

With this project, studies in the field of molecular inorganic chemistry are proposed. The study of heavy multiple bond systems a part of this discipline, and continues to be of interest because they can be applied in the activation of small molecules such as CO2 or H2, serve as ligands for transition metal complexes and even be catalysts themselves, for instance for the cyclotrimerisation of alkynes. Their synthesis commonly requires sterically demanding groups for kinetic and thermodynamic stabilisation. With the N-aminated carbazolyl group developed in our group, initially, the stabilisation of novel imino(halo)phosphines is now proposed, as this substituent enables the modulation of bond order of the multiple bond system by electron delocalisation from and into the carbazol scaffold. The halide functionality allows various methods for the derivatisation of this unusual class of compounds. The first work package is aimed at exactly that: By halide abstraction, reduction or metathesis reactions, other molecules with P-N multiple bond shall be generated. Those can, in dependence of their bonding situation, show special reactivity which will always be studied in parallel to the synthetic efforts. The second work package combines halide abstraction from imino(halo)phosphines with the reaction with organoazides, targeting the synthesis of a molecule featuring a P(V) atom with coordination number 2. For this species, significant Lewis acidity can be expected which is going to be exploited for small molecule activation. The third work package is set to extend the synthetic methodology to the heavier group 15 elements. To date, isolable imino(halo)arsines are unknown, but they could be sufficiently stabilised by the carbazolyl substituend to allow their isolation. Thus, a new field in molecular chemistry would be opened up, and various subsequent reactions in analogy to the former two working packages are imaginable. The first working package is plannable within the bounds of exploratory synthetic chemistry, but the second and third working package have a high-risk-high-reward profile, and the goals are harder to achieve. They, in turn, have the potential for significant progress in main group molecular chemstry. Already in this project, new multiple bond systems will be made accessible, and their reactivity promises the discovery of varied patterns. The project will yield transferable methods of synthesis that can render various reactive molecular species accessible in the long term.

• DFG Programme: Research Grants