SuprAlloCat · Nanostructured Supramolecular Polymers with Allosterically Regulated Catalytic Interstices

Nanostructured Supramolecular Polymers with Allosterically Regulated Catalytic Interstices

-The extraordinary biological importance and impressive performance of (metallo)porphyrins in energy-related molecular activation reactions have attracted the interest of scientists from diverse fields. Increasingly sophisticated synthetic models of the heme iron porphyrin have been used to understand this complex coordination chemistry and to prepare homogeneous biomimetic catalysts. A more recent trend aims at controlling the self-assembly of porphyrinoids to produce a new family of nanoporous metal-organic frameworks (MOFs) or covalent organic frameworks (COFs) that can function as heterogeneous (photo/electro)catalysts. However, the primary self-assembly driving forces involved in the formation of MOFs and COFs based on porphyrins usually include axial coordination and cofacial π-π stacking, respectively. This is a big problem because, with the exception of the molecules sited at the crystal edges, the axial active sites around the metal center are not exposed to the relevant reagents, drastically decreasing their catalytic properties. In this project we combined the versatility and robustness of the self-assembly approach shown in both COFs and MOFs preparation, with the well-defined nanocavities present in biological enzymes, that are responsible for accessible active sites, to prepare nanostructured systems based on co-facial (metallo)porphyrins which exhibited relevant host-guest properties, chiral induction, allosteric effects, and potential catalytic applications. -The severe energy crisis due to the massive consumption of fossil fuels and the considerable global population growth, together with the more than evident environmental impact caused by the last two, make extreme urgency for our present society the development of a complementary set of sustainable energy and raw material resources for both the economic and the ecological point of view. Therefore, the implementation of this kind of molecules in nanostructured systems that present an accessible catalytic pocket could result in great importance in order to achieve the same level of performance as Nature does in the very relevant field of catalysis. -In this context, in SuprAlloCat we plan to apply some of the lessons learned from nature to target the noncovalent construction of unprecedented nanostructured supramolecular polymers with catalytic performance that would combine the broad catalytic scope of homogeneous catalysts, and the allosteric control, selectivity and activity under mild conditions of enzymes. The key to achieving such a goal relies on the development of a self-assembly strategy that will allow us to cofacially arrange metalloporphyrins at tailored interstitial distances along different dimensions, thus creating a periodic array of connected nanoreactors with well-defined, accessible (photo)catalytic sites. These self-assembled compartmentalized materials can serve as catalysts for manifold relevant chemical transformations, and in particular for regio- and enantioselective epoxide ring-opening reactions using Lewis-acid based catalysis.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз