Catalysis of phosphorus materials

Dr. Christian Hering-Junghans

Catalysis is a powerful tool to achieve the goals accompanied with “greener“ environmentally benign processes, as it is the science of accelerating chemical reactions. One of the principles of “Green Chemistry” is the use of renewable raw materials or feedstock instead of depleting ones whenever technically and economically practicable. Consequently the focus of our research is on the design of new and efficient methods to form C-N bonds directly from atmospheric nitrogen. These bonds are ubiquitous in nature and in combination with abundant, non-organic carbon sources such as CO2 or CO, C-N bond forming reactions offer fascinating opportunities to make fine and commodity chemicals in a more sustainable way. In this context we are concerned with the design of state-of-the-art ligand systems for efficient stabilization of low-valent early transition metals. Here the focus will be on the effective steric shielding of the metal center and on the other on the investigation of the electronic nature of the ligand. It is envisaged to use the ligand as an electron reservoir. We seek employ modern element-organic methods in combination with classic coordination chemistry techniques. The fundamental properties of our systems will be uncovered using comprehensive characterization methods. The overall basis for our approach in ligand design will be the structure of the FeMo-cofactor in the enzyme nitrogenase in order to realize biomimetic reactivity. 

Another area of research is the chemistry of so-called phosphanylidenephosphoranes and their heavy homologs. These systems can be regarded as phosphane-stabilized phosphinidenes and novel ways of phosphinide transfer are investigated. On the one hand, the activation of strong chemical bonds (e.g. C-H, N-H, etc.) are investigated and thus new phosphorus-containing materials will be studied in detail. Moreover, it is possible to exchange the phosphane in a substitution reaction, allowing facile synthetic access to a variety of compounds (Scheme 2).


We have shown that phosphanylidenephosphoranes with small groups on the phosphorus cannot be prepared, and instead cyclotriphosphanes of the type P3Ar3 are selectively obtained. We are also using these as a phosphinidene sources, investigate their reactivity towards early transition metals and in cyclization reactions to obtain new P-containing materials and ligands.

Another project deals with the synthesis of Grupp 13-15 multiple bond systems and their reactivity towards small molecules. The focus here is on the synthesis of so-called phospha- and arsaalumenes, which are heavy homologs of alkenes. In this project, both cyclotriphosphanes and phosphanylidenephosphoranes are used to realize effective phosphinidene transfer to aluminum compounds in the +1 oxidation state (Scheme 3).



Students with special interest in inorganic synthetic chemistry, ligand design and the application of metal complexes in small molecule activation are welcome to join the group in the framework of internships, bachelor and master theses. In addition, suitable candidates are encouraged to contact Dr. Christian Hering-Junghans regarding PostDoc fellowships.

Please send an email to Christian.Hering-Junghans{at}