Preparation, characteristics and crystal structures of novel N-heterocyclic carbene substituted furan- and pyridine-containing azadithiolate Fe–S complexes

Two novel N-heterocyclic carbene disubstituted furan- and pyridine-containing azadithiolate Fe-only hydrogenase models (2 and 4) have been synthesized, and characterized by IR and 1H NMR spectra and X-ray single crystal diffraction. Cyclic voltammetry (CV) experiments indicate that they show more negative reductive potentials at −2.53 V and −2.49 V, respectively versus the ferrocene/ferrocenium couple (Fc/Fc+) and are easier to capture proton attributing to the strong electron-donating ligand NHC. After the protonation under F3CCO2H the reductive potentials of 2 and 4 have 1.02 V and 0.77 V shifts, indicating the formation of Fe–H–Fe bond. The results also are confirmed by the data changes in IR spectra and the negative H signals are detected by 1H NMR spectra at −27 ppm and −55 ppm.

Two novel N-heterocyclic carbene disubstituted furan- and pyridine-containing azadithiolate Fe-only models have been synthesized and characterized. They show more negative reductive potential and are easier to capture a proton attributing to the strong electron-donating ligand NHC.Figure optionsDownload as PowerPoint slide