Exploring the chemistry of the new phosphine CAP: from catalytic to medicinal application

For many years, most of our research activity has been focused on the synthetic modifications and coordination properties of the cage aminophosphine PTA (1,3,5-triaza-7-phosphadamantane), achieving good results in the field of water phase or aqueous biphasic homogeneous catalysis. More recently, we started to explore the chemistry of a higher homologue of PTA, i.e. 1,4,7-triaza-9-phosphatricyclo[5.3.2.1]tridecane (CAP) that despite the structural similarity, showed many differences in terms of reactivity.Taking into account our expertise on ruthenium PTA chemistry, we synthesized three novel Ru(II)-arene complexes in which CAP binds the metal in K1-P fashion, that showed good activity in homogenous transfer hydrogenation of C=C and C=N bonds under very mild conditions. The same complexes were tested in vitro against selected cancer cell lines, revealing higher activity than the corresponding well-known RAPTA compounds. Finally, interesting results on catalytic C?N bond hydration using new Ru-CAP complexes were very recently obtained and will be also presented.The DSCTM-CNR is kindly acknowledged for financial support through the YIA2018 award to A. G.