Synthesis and NMR study of paramagnetic pyridine-based NAMI-A-type ruthenium complexes

Martin Sojka ^a,b^ *, Jan Novotný ^b, Radek Marek ^a,b, Marek Nečas ^a,b


^a Department of Chemistry,  Masaryk University, Kotlářská 2, 61137 Brno, and ^b CEITEC – Central
European Institute of Technology, Kamenice 5, 62500 Brno, Czech Republic
* martin.sojka@mail.muni.cz

We are interested in the synthesis of new Ru(III)-based complexes with promising anticancer
activity. The paramagnetic nature of Ru(III) compounds  usually makes routine 2D NMR experiments
inapplicable and complicates the unambiguous interpretation of 1D NMR spectra. Thus, the assignment
of experimentally detected ^1H and ^13C NMR resonances is performed with close support of advanced
quantum-chemical calculations.

Hereby we report a study of NAMI-A-type Ru(III) complexes with selected pyridine derivatives. For
our NMR experiments we synthesized a series of Ru(III) complexes with pyridine ligands (Figure 1)^1
and  their Rh(III) analogs. To determine the temperature-independent part of the NMR chemical shift
(orbital contribution) we performed temperature-dependent NMR experiments and characterized the
closed-shell Rh analogs. The experimental values will be compared with theoretical data obtained
from DFT calculations employing SO-ZORA approximation and implicit model of solvent.

Figure 1 General synthetic approach for synthesis of Ru(III) NAMI-A-type complexes


This work was supported by the Czech Science Foundation (15-09381S).


1 M. I. Webb, R. A. Chard, Y. M. Al-Jobory, M. R. Jones, E. W. Y. Wong, C. Walsby, Inorg. Chem.
2012, 51, 954.