Sustainable synergistic iron - organocatalysis for epoxy carboxylic acid reactions
Materials are coated to protect them or make them more visibly appealing. In the coating process, high temperatures are often needed, which takes a lot of energy and makes it less suitable for some materials (such as wood or plastic). In his research, Tizian Ramspoth worked on catalysts that enable coating at lower temperatures, which would make the process more sustainable and more widely applicable.
In particular, Ramspoth focused on the development of sustainable and efficient cooperative catalyst systems for the ring opening reaction of epoxides by carboxylic acids. He identified FeCl3/DMAP as a potent catalyst system, which functions via a simultaneous activation of both the epoxide and the carboxylic acid. He then developed two highly efficient cooperative catalyst systems, which are based on [Fe3O(Benzoate)6(H2O)3]NO3 as halide free, sustainable iron source.
In conjunction with guanidinium carbonate (GC), the catalyst system has similar activity as the previously identified FeCl3/DMAP system in toluene and maintained its effectivity in anisole as a sustainable solvent alternative. The system is non-toxic, recyclable, sustainable and behaves superior to currently employed catalysts in the synthesis of 2-hydroxy-3-phenoxypropyl methacrylate, an industrially relevant photosensitive monomer.
A second developed [Fe3O(Benzoate)6(H2O)3]NO3/PPh4Br catalyst system exceeded the catalytic activity of the FeCl3/DMAP system and showed improved performance over industrial state of the art catalysts in gel time experiments of powder based thermosets at 140 °C and 170°C, as well as acceptable curing times at 120 °C.