Ag/Pd Cocatalyzed Direct Arylation of Fluoroarene Derivatives with Aryl Bromides

Adyasha Panigrahi; Daniel Whitaker; Iñigo J Vitorica-Yrezabal; Igor Larrosa

doi:10.1021/acscatal.9b05334

Ag/Pd Cocatalyzed Direct Arylation of Fluoroarene Derivatives with Aryl Bromides

ACS Catal. 2020 Feb 7;10(3):2100-2107. doi: 10.1021/acscatal.9b05334. Epub 2020 Jan 9.

Authors

Adyasha Panigrahi¹, Daniel Whitaker¹, Iñigo J Vitorica-Yrezabal¹, Igor Larrosa¹

Affiliation

¹ School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.

Abstract

Diverse C-H functionalizations catalyzed by Pd employ Ag(I) salts added as halide abstractors or oxidants. Recent reports have shown that Ag can also perform the crucial C-H activation step in several of these functionalizations. However, all of these processes are limited by the wasteful requirement for (super)stoichiometric Ag(I) salts. Herein, we report the development of a Ag/Pd cocatalyzed direct arylation of (fluoroarene) chromium tricarbonyl complexes with bromoarenes. The small organic salt, NMe₄OC(CF₃)₃, added as a halide abstractor, enables the use of a catalytic amount of Ag, reversing the rapid precipitation of AgBr. We have shown through H/D scrambling and kinetic studies that a (PR₃)Ag-alkoxide is responsible for C-H activation, a departure from previous studies with Ag carboxylates. Furthermore, the construction of biaryls directly from the simple arene is achieved via a one-pot chromium tricarbonyl complexation/C-H arylation/decomplexation sequence using (pyrene)Cr(CO)₃ as a Cr(CO)₃ donor.