Ru, Ir and Rh-catalysed processes in Water and Biphasic Media using Amphiphilic Aminophosphines

In the last decade, our research group has been active in the field of water-phase and biphasic catalytic processes involving transition metal centres stabilized by the neutral water-soluble and air-stable monodentate aminophosphine PTA (1,3,5-triaza-7-phosphaadamantane). In particular, we have obtained several functionalization of PTA, such as on the "upper rim" 6-position and on the "lower rim" by N-alkylations, resulting in a library of derivatives for different applications. In this overview, a summary of the main results will be presented, in particular related to: a) Homogeneous C=C and C=O bond hydrogenations catalysed by Ir(I) and Ru(II) complexes bearing "upper rim" modified PTA; b) Biphasic "on water" Rh-catalyzed hydroformylations of long-chain olefins using N-benzylated "lower rim" PTA derivatives in the presence of randomly methylated ?-cyclodextrins (RAME-?-CD), allowing for a thermocontrolled process with rapid decantation of the biphasic system at the end of the reaction maintaining high regioselectivity and activity at moderate temperatures (Figure 1); c) Heterogeneous C=N and C=O hydrogenations of water soluble substrates under mild conditions, using an Ir-PTA complex immobilised onto commercial ion-exchange resins.