Advanced Synthetic Strategies for the preparation of Key Small Molecules and Biologically Active Compounds

The present manuscript gathers many topics I dealt with during my PhD research period. The first chapter includes an overview on how sustainability is getting more and more relevant in chemistry and, in particular, in the development of chemical processes, since the outbreak of Green Chemistry concepts until now. Moreover, some of the most important enabling technologies in organic synthesis are detailed, such as one-pot processes, microwave irradiation, flow chemistry and photochemistry, with a final section dedicated to combined techniques. The second and third chapters encompass the research work I conducted at University of Camerino (Chemistry Interdisciplinary Project, ChIP, Camerino, Italy) in the Green Chemistry Group, under the supervision of Prof. A. Palmieri, with the collaboration of Indena S.p.A., and in Prof. C. O. Kappe’s research group (CCFLOW lab) from April 2022 to October 2022, at the University of Graz, Institute of Chemistry, under the supervision of Dr. C. Hone. In particular, the second chapter focuses on the importance of nitro compounds as key building blocks in organic synthesis. In this context, nitroolefins were exploited, during my PhD, to achieve the synthesis of polysubstituted carbazoles and conjugated (E,E)-dienones under mild conditions, two important compounds that find application in drug molecules and materials science. Furthermore, their hydroalkylation was accomplished under photocatalytic conditions, both in batch and flow, in a project conducted in collaboration with the PhotoGreen Lab of University of Pavia. The third chapter is devoted to explore the relevance of natural products in organic chemistry, with particular attention on the development of synthetic procedures to access valuable compounds. With this aim, we envisaged a simple four-step sequence for the preparation of flavonoid Luteoloside, often present in natural sources only in traces, in the context of a project carried out in collaboration with Indena S.p.A. The last section of the chapter describes the work realized during my abroad period at the University of Graz, in which a continuous flow protocol was developed, after an extensive batch investigation, for the selective synthesis of two cannabinoids, Δ9 -THC and Δ8 -THC.