This project aims at exploiting the high electrophilic character of high valent gold(III) species for C–H activation to develop new transition metal catalytic systems based on gold for a major scientific challenge in modern chemical synthesis that is the selective transformation of ubiquitous hydrocarbon compounds into high added value functionalized molecules. Two main strategies will be explored for the development of gold catalyzed C-H functionalization reactions: The first approach concerns the development of direct arylation of arenes and alkanes via Au(I)/Au(III) redox catalytic cycles. In this original approach, the key gold (III) species will be generated in mild conditions by oxidative addition of aryl halides to gold(I) complexes, and the high valent gold electrophilic gold species will be reacted with arenes first, and then with more challenging Csp3–H bonds. The C-H activation step will be investigated in details to delineate the reactivity/selectivity of these gold(III) species. Here, the steric/electronic effect of the ancillary ligand at gold will be an advantage to fine-tune the electrophilic character of gold(III). Thus, mechanistic investigations on this original catalytic pathway involving oxidative addition, C-H auration and reductive elimination will help to define the optimal conditions for viable catalytic formation of C-C bonds. These gold species will be applied to catalytic late stage C-H bond functionalization. The second approach will consists in the use of well-defined gold(III) complexes for the oxidative functionalization of Csp3–H bonds, with the ultimate goal being the functionalization of light alkanes. In this part, we will particularly explore the reactivity of these gold(III) species in the presence of strong oxidant, and notably the possible involvement of unknown gold(V) species in the C-H bond functionalization process. The synthesis of model organogold compounds and precise mechanistic investigations will provide key informations into the feasibility of the process and document the development of gold(III) catalyzed functionalization of alkanes.
Monsieur Abderrahmane AMGOUNE (Université Claude Bernard Lyon 1 -Institut de Chimie et de Biochimie)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
ICBMS Université Claude Bernard Lyon 1 -Institut de Chimie et de Biochimie
CNRS/LHFA Centre National de la Recherche Scientifique/Laboratoire Hétérochimie Fondamentale et Appliquée (UMR CNRS 5069)
Help of the ANR 218,837 euros
Beginning and duration of the scientific project: September 2016 - 48 Months