Synthetic organic compounds are essential to our society’s way of living and its economic growth. It influences all aspects of our lives, including healthcare, agriculture, well-being, and food industries. Because of limited natural resources, developing novel strategies to efficiently access function-tailored chemical entities with lower ecological and economic impacts represents a fundamental goal of modern organic chemistry. Transition metal catalysis is crucial in achieving this sustainable goal. It offers unique mechanistic opportunities to access compounds that are difficult to obtain by conventional means, lowers the reactions’ activation barriers, and improves their selectivity, rendering the transformations less energy-intensive and more efficient. Despite the incredible achievements in synthetic organic chemistry granted by transition metal catalysis, two pressing challenges must be addressed to meet green chemistry’s objectives. First, one must reduce the reliance on precious transition metals that are expensive and in short supply. In this context, earth-abundant transition metals are a more appealing alternative to the commonly used precious metals in terms of price, availability, carbon footprint, and toxicity. Second, most transition metal-catalyzed transformations require starting materials possessing preferential functional groups (e.g. halides). Installing these functional groups implies additional synthetic steps, making the overall transformation less atom-economical. Thus, new synthetic strategies catalyzed by earth-abundant transition metals that involve commonly occurring functional groups (e.g. C-H bonds, carboxylic acids) are highly sought after.
The overarching goal of the proposal is to develop and study innovative synthetic methodologies involving C-H bond functionalization with catalyst-based transition metals (Co, Cr, Ni) to access new or existing organic compounds from widely available starting materials while ensuring a selectivity control of which bond will be activated. The MLCat will solve the selectivity and reactivity problem associated with the C-H functionalization reactions with transition metals. The materialization of this concept requires the use of multifunctional ligands and a bimetallic catalytic system. The project relies on arenes’ ability to form π-complexes with Cr(0) that drastically activates the aromatic ring, rendering the C-H bonds more acidic towards the C-H activation. Our ultimate goal entails generating a catalytic amount of π-chromium-arene complex that will facilitate the functionalization of C-H of the aromatic ring with the assistance of the second transition metal responsible for the C-FG bond formation.
