Seminar Pr Manfred SCHEER

Pr Manfred SCHEER

Institute of Inorganic Chemistry, University of Regensburg,
93040 Regensburg, GERMANY
manfred.scheer@chemie.uni-r.de

The Magic of Polypnictogen Compounds

Polyphosphorus units are an important class of compound and isolobal to carbon-based relatives. Because of the lone pairs at the phosphorus atoms, the fivefold symmetric cyclo-P5 ring of the pentaphosphaferrocenes [CpRFe(η5-P5)] enables the use of these complexes in unique supramolecular aggregations with Lewis acidic transition metal moieties to form unprecedented giant spherical molecules (Figure 1, left).1 The talk will show versatile ways of the reactivity of this interesting class of compounds regarding their redox behavior2 as well as their ability to be converted by both nucleophiles and electrophiles (Figure 1, right top). Concerning the redox properties, novel insights into E-E bond formation and breaking are presented. The frontier orbitals of polypnictogen ligand complexes show clearly the ability to be converted by both nucleophiles and electrophiles. Therefore, novel ways of access to substitution reactions3 and subsequent quenching result in unique pathways for the selective formation e.g. of asymmetric phosphines (Figure 1, right bottom).

Figure 1. Versatile reactivity of [CpRFe(η5-P5)]: left) giant supramolecular sphere; right top) Redoxchemistry of pentaphosphaferrocene, its nucleophilic modifications and electrophilic quenching; right bottom) semi-‘catalytic’ cyclic process for asymmetric phosphines

References

(1) C. Heindl, E. V. Peresypkina, A. V. Virovets, W. Kremer, M. Scheer, J. Am. Chem. Soc. 2015, 137, 10938.
(2) S. Reichl, F. Riedlberger, M. Piesch, G. Balázs, M. Seidl, M. Scheer, Chem. Sci. 2023, 14, 7285 – 7290.
(3) S. Reichl, E. Mädl, F. Riedelberger, M. Piesch, G. Balázs, M. Seidl, M. Scheer, Nat. Commun. 2021, 12, 5774.