Bismuth redox catalysis for sustainable organic synthesis
Homogeneous catalysis based on transition metals has become an indispensable strategy in the development of efficient methodologies for organic synthesis, finding application in a wide variety of processes across the chemical sciences. Inspired by the wealth of reactivity in this area, we present a proposal that departs from transition metal catalysis and aims at unlocking the potential of bismuth (Bi) as a sustainable catalyst, unravelling novel and unknown catalytic redox processes for organic chemistry. The main goal of this project is to translate the unique properties traditionally associated to transition metals to a main group element. Let-it-Bi is a quest to disclose the remarkable potential of a commonly overlooked element of the periodic table such as bismuth, in the field of catalysis and organic synthesis. Being an earth abundant, non-toxic and inexpensive element, bismuth represents an excellent candidate to be explored in catalysis and to study its fundamental reactivity. In the first part of this proposal, we describe the design of a novel Bi(III)⇄Bi(V) redox cycle towards the formation of synthetically relevant and challenging C‒C, C‒Halogen, C‒N and C‒O bonds. The last part proposes the expansion of this concept to an unprecedented Bi(I)⇄Bi(III) redox cycle. Such a unique redox system will find application in the activation of small molecules (H2, NH3, B‒H and Si‒H bonds) for the functionalization of simple and largely available olefins. In addition to provide a solution to the price, toxicity and environmental issues associated to transition metal-based transformations, this proposal aims at the exploration of uncharted territories in the area of homogeneous catalysis; thus discovering and providing novel reactivities for organic synthesis which remained elusive to date. Noteworthy, preliminary results accompany both parts demonstrating the feasibility of the proposed research.