The Department of Inorganic Chemistry kindly invites to the following Talk:

Prof. Dr. Wolfgang Weigand, Friedrich Schiller University, Jena, Germany

"The Potential Role of Iron Sulfide in the Prebiotic Chemistry"

The reaction of elemental iron and sulfur in water at room temperature is known since many years,
although the characterization of the formed iron sulfide was still pending. We could show by use of
diffraction methods that mackinawite (FeS) was formed under these exceptionally mild reaction
conditions.¹ Iron sulfides also form the central components of the much-discussed theory of a
chemoautotrophic origin of life in a primordial iron sulfur world.²
Mackinawite prepared after that protocol is highly reactive and it was found to reduce cyanide
yielding a variety of organic sulfur compounds, alkyl thiols, alkyl di- and trisulfides, sulfur containing
heterocycles like 1,2,4-trithiolane as well as carbon disulfide. The identification of the products was
confirmed by GC-MS techniques and the carbon-carbon bond formations have been confirmed by
use of 13C isotope labelling experiments. Moreover, the constituents of the aqueous phase were
characterized by using NMR spectroscopy.³
This reaction could be of primordial relevance because compounds are formed which are important
for the origin of biologically relevant building blocks.⁴

References
[1] R. Bolney, M. Grosch,M. Winkler, J. van Slageren, W. Weigand, C. Robl, RSC Adv. 2021, 11, 32464.
[2] G. Wächtershäuser, Prog. Biophys. Mol. Biol. 1992, 58, 85-201.
[3] M. Grosch et al., ChemSystemsChem 2022, e202200010.
[4] W. Martin, M. J. Russell, Phil. Trans. R. Soc. B 2007, 362, 1887-1925.