In 2011, the second generation of Togni reagents were discovered at ETH Zurich and IOCB Prague and patented in 2014. The extremely versatile chemistry of CF3-Togni reagents developed over the last 12 years is enriched by another dimension provided by the second generation Togni reagents as these compounds can transfer a wide selection of RCF2CF2 fragment using practically the same reaction conditions developed for the first generation of Togni reagents. The second generation of Togni reagents thus constitutes a powerful tool how to easily incorporate various RCF2CF2 units to molecules of interest in late stages of synthesis.
In 2015, IOCB and CF Plus Chemicals discovered and patented a straightforward, scalable process how to synthesize trifluoromethyl azide and other related perfluoroalkyl azides, such as pentafluoroethyl azide. Although trifluoromethyl azide and pentafluoroethyl azide represent rather understudied exotic compounds, we demonstrated that they can be safely prepared, handled and utitized in the well-established copper catalyzed alkyne-azide cycloaddition, providing regioisomerically pure N-perfluoroalkyltriazoles which would not be easily accessible by other methods. The resulting N-perfluoroalkyltriazoles can be also transformed to related N-CF3 heterocycles based on Rh-carbene chemistry.
Simple access to these potentially attractive heterocycles can provide a tool how to modulate the behaviour or drug candidates in a variety of ways, for example to replace a metabolically weak N-CH3 compounds by a more robust N-CF3 derivatives. Compared to other alternatives, our technology based on perfluoroalkylazide thus represents a much more straightforward and operationally simple access to a broad variety of N-perfluoroalkyltriazoles.
In 2018, we added to our portfolio difluoromethylazide. Difluoromethylazide shares practically the same reactivity as trifluoromethylazide in copper catalyzed alkyne-azide cycloadditions, providing expedient access to five-membered N-CF2H heterocycles which are highly attractive for medicinal chemistry discovery programmes. Difluoromethylazide provides similar synthetic benefits as other fluoroalkylazides - a broad substrate scope of regiochemically defined N-difluoromethylazoles can be accessed in a much simpler manner than with other synthetic routes.