Our research

Our current research is directed towards the development of new N-heterocyclic carbenes (NHCs). Our special interest is focused on electron poor NHCs that are able to exert a significant degree of π-acceptor character when coordinated to transition metal centres. This propensity for π-backbonding has been neglected for a long time and is not observed for standard NHCs like N-arylimidazolylidenes.

In addition to sketching down appealing new structural motifs on a piece of paper our work usually requires multistep organic syntheses to derive at suitable carbene precursors which can be converted to appropriate NHC derivatives upon deprotonation and scavenging the in situ-formed NHC with trapping reagents.

The electronic properties of the new NHCs are derived from spectroscopic (NMR, IR) and structural (X-ray diffraction) data. For example, we have developed a method for the assessment of the π-acidity of NHCs by recording the ⁷⁷Se NMR shifts of their selenium adducts. Increasing π-acidity is accompanied by a low-field shift of the ⁷⁷Se NMR resonance.

1   M. Jonek, J. Diekmann, C. Ganter, Chem. Eur. J. 2015, 21, 15759-15768.  externer Link in neuem Fenster

2   T. Hölzel, M. Otto, H. Buhl, C. Ganter, Organometallics 2017, 36, 4443-4450. externer Link in neuem Fenster

3   S. Appel, P. Brüggemann, C. Ganter, Chem. Commun. 2020, 56, 9020-9023. externer Link in neuem Fenster

4   P. Brüggemann, M. Wahl, S. Schwengers, H. Buhl, C. Ganter, Organometallics 2018, 37, 4276-4286. externer Link in neuem Fenster

5   A. Liske, K. Verlinden, H. Buhl, K. Schaper, C. Ganter, Organometallics 2013, 32, 5269-5272. externer Link in neuem Fenster

We are also interested in luminescent NHC-copper complexes, especially those with a linear coordination environment around the Cu atom. We aim at a detailed understanding of the factors determining emission wavelength, quantum efficiency and radiative lifetimes, to name but a few. A multidisciplinary and collaborative approach is followed where synthesis and the experimental determination of photophysical properties are complemented by high-level quantum theoretical calculations – which in turn stimulate the synthesis of new structures with (hopefully) improved performance.