Skip to main content

Green enantioselctive catalyst for continuous asymmetric precesses in supercritical fluids

Final Activity Report Summary - GRE-ENCAT (Green enantioselctive catalyst for continuous asymmetric precesses in supercritical fluids)

This project addresses the challenges of designing new green asymmetric processes based on the combination of heterogeneous asymmetric catalysts and supercritical fluids, which provides cleaner processes for synthesis of enantiopure compounds in the absents of organic solvents, and develops cleaner routes for manufacturing highly added value products. Taking into account established goals a number of successful results have been achieved. A continuous flow reactor was developed in such a way that it could be easily adjusted for the specific task reactions. The rig was designed to accommodate mini-flow reactors based on monolithic materials with a required functionality.

These catalysts are based on the use of polymeric monolithic materials. Different mini-flow reactors with variety of chiral functionalities (pybox and bisoxazoline) and morphologic characteristic were prepared. The preparation of the monolithic reactor was carried out by thermally induced bulk polymerisation of the chiral monomers and co-monomers in a stainless steel column. Once different columns were prepared, the benchmark reaction in scCO2 investigating the influence of different factors such as residence time, pressure or CO2/organic ratio was carried out. Another research line was the development of new generation of advanced materials tailored at a nanoscale level.

We have designed supported structured reagents and / or catalysts at two different levels. A first level provides the structural requirements needed flow-through process and a second one a molecular and nanoscale level.

A second degree of organisation is introduced by a further modification of these constrained spaces by introducing appropriated modifiers. The modifiers are ionic liquid (IL)-like functionalities, which modify the nature of the material transferring the ILs properties at molecular and nanoscale level. These IL-like units were imidazol groups. Polymerisable IL-like monomers can be used to graft IL-like chains to the performed material. Both grafting approaches are highly versatile. Thus, the properties of final support can be easily tuned by varying type of material, IL-like group, anion, etc.