Invited
Nitrogen cations as ligands and Lewis acids

In this lecture we will demonstrate that nitrenium cations, which are isostructural and isoelectronic to ubiquitous N-heterocyclic carbenes, can serve as ligands for a wide range of transition metals.¹ It represents a missing link in the coordination behavior of carbenes and other main group carbene-like species. The chemistry of these systems and its relevance to catalysis will be discussed. Formation of a stable bond between the positively charged nitrenium ligands and cationic metal centers, providing an extremely rare example of cation-cation binding, will be also presented and discussed.² In addition, we will disclose a first X-ray supported example of Lewis acids centered on nitrogen atom.³ Properties of a new class of nitrogen based Lewis acids will be presented.

¹ Nature Chem. 2011, 5, 525.

² Chem.Sci. 2014, 5, 1305.

³ J. Am. Chem. Soc. 2017, 139, 4062.