Jagadeesh Varma Nallaparaju

This Centre of Excellence (CoE) focuses on fostering innovation in resource efficiency, promoting circular economy practices, utilizing local resources, ensuring safe material circulation, and educating researchers to reduce environmental impacts. It centers around four key areas: Strategic Mineral Resources (SMR), Carbon-Based Resources (CBR), Circular Technologies Upscaling (CTU), and Circular Business Eco-System and Modeling (CBEM). The SMR group maps critical materials in waste streams, including renewables, for extraction and reuse while minimizing hazardous waste. The CBR group develops ecofriendly pathways for essential chemicals and plastics, also assessing their environmental impact. The CTU group pioneers waste reduction and recycling methods for aqueous, and solid waste, incl. water purification. The CBEM group analyzes sustainable business ecosystems and value chains. This CoE's interdisciplinary approach will benefit both Estonia and Europe by advancing circular economy.

Sensing, capturing and separating enantiomers is important for environmental safety, agricultural chemistry, and drug design. The use of hemicucurbiturils is an effective strategy because of the combination of various monomers in a single-step templated mechanochemical synthesis. Due to the absence of bulk solvent the self-organizing efficiency is amplified and there is less waste - the process is green and sustainable. The current work will study the fundamentals of self-organization of hemicucurbiturils, the binding (capturing) of chiral molecules, and detecting chirality using supramolecular complexes. In the long term, the empirical observations will be combined with results from computational chemistry and cheminformatics to build models for predicting necessary monomers and reaction conditions to form macrocycles with desired properties. The outcomes of the project are expected to be highly useful for organizations and industries that monitor, use, or manufacture chiral compounds

Development of adaptable supramolecular chirality sensors is important for the industry and academia. Chiral molecules, in nform of enantiomers, are commonly used in the pharmaceutical, food, perfume, cosmetic, and agricultural industries. In biological ecosystems, chiral molecules are metabolized, absorbed, and excreted selectively, and their biological effects can vary significantly. Therefore, the environmental impact of different stereoisomers can be radically different. Standard analysis methods that do not distinguish the chirality of molecules may underestimate the effects of these compounds. In this project, we designed and synthesized new receptor molecules through both supramolecular interactions and covalent bonding. By investigating the structure, optical, and supramolecular properties of the obtained receptor molecules, we reached several new compounds with the potential to be applied for separation, isolation, and detection of bioactive compounds and environmental pollutants. We developed environmentally friendly mechanosynthesis methods to reduce waste production during the synthesis process of organic compounds. Additionally, we studied formation of oligomeric macrocyclic receptors and developed methods for obtaining both mono- and multifunctional macrocyclic compounds. We initiated research on the creation of supramolecular materials and demonstrated that materials for enantioselective electronic noses can be easily prepared using porphyrins and chiral hemicucurbiturils. We also investigated the correlation between the circulardichroism signal generation and molecular orbitals and geometries modelled by quantum chemical methods. We also showed that the signal of the studied optically active sensor molecules can be amplified via interaction with inorganic chiral materials. The results of the project were published in number of research articles and two patents were applied for.