New catalytic strategies for the synthesis of complex (hetero)-cyclic compounds

The aim of this Doctoral Thesis is the development of new catalytic transformation for efficient and sustainable processes, with the main purpose of easily access the incredible diversity and complexity of bio-relevant compounds. The tuning of general synthetic strategies is a flourishing field in organic chemistry, and can rapidly give access to libraries of products with small to big modifications from a hypothetical lead compound. Whit this in mind, in the modern era of organic synthesis, many aspects are pivotal in the design of a new catalytic procedure, such as reproducibility, generality over the main functional groups, mild conditions and easily accessible starting materials and catalysts. Particularly, another fundamental aspect is the generation of complexity in one single step, to conveniently assemble the scaffold of the class of compounds studied. During the course of my PhD, two main strategies were analyzed to tackle these challenges, namely de-aromatization and ring construction through cyclization. These methodologies have been deeply investigated both in organo- and metal-catalyzed fashions, and conceptually new protocols have been developed. Particular attention has been devoted at the study and optimization of the reaction conditions and catalyst structure, in order to maximize yield and selectivity of the processes as well as minimizing the catalyst loading and using the mildest conditions. The substrate scope has been thoroughly investigated to demonstrate the broad applicability of the proposed transformations, as well as the performance of synthetic elaborations illustrating the usefulness of the developed methods. Despite the conceptual diversity, the proposed protocols are connected by their potential further development into useful tools for the bio-molecule synthetic scenario.