HYPervalent IodoSULfoximines as new perfluoroalkylating reagents – HYPISUL

The goal of this research proposal is firstly to synthesize a new family of compounds, the hypervalent iodosulfoximines, and secondly to study their properties especially as electrophilic (enantioselective) sources of perfluoroalkyl moieties as well as a source of fluorinated radicals.
The group of A. Togni already developed two hypervalent iodine species which are now amongst the most useful and versatile reagents for the trifluoromethylation of a great variety of substrates, from small building blocks to more elaborated compounds. These reagents are fully integrated in the arsenal of chemists (not only those specialized in fluorine chemistry) and are worldwide well known and commercially available.
We propose to extend this family of reagents in order to improve their field of application. Two directions will be explored: 1) the improvement of their reactivity and 2) the modification of the reactive unit they can deliver. This will be done by introducing into the basic molecular skeleton an S-perfluoroalkyl sulfoximine, a recently emergent group displaying intriguing and promising qualities. The replacement of the “acid” part of one of the Togni reagents by a sulfoximine function will allow a modification of the electronic properties of the iodine atom. It should then allow the introduction of original fluorinated entities such as e.g. SCF3 and OCF3 on the hypervalent iodine close to a stereogenic center, the sulfur atom of the sulfoximines.
We propose to divide the project into three work packages. The first one will be mainly devoted to the preparation of new compounds, including their enantiopure version, this being the task of the French partner. The second one will consist in the development and the study of their properties, in particular as vector of fluorinated moieties, both electrophilic and radical. This task is assigned to both partners. The third work package will consist in theoretical, structural and mechanistic studies in order to gain deep understanding, thus serving as guide for the project. This last task is totally assigned to the Swiss partner.
Close collaboration between the two groups will ensure a rapid progress by merging two different but highly complementary skills in fluorine chemistry.