STAR Protocols (Sep 2022)
A ligand-enabled metallaphotoredox protocol for Suzuki-Miyaura cross-couplings for the synthesis of diarylmethanes
Abstract
Summary: Here, we present a ligand-enabled metallaphotoredox Suzuki-Miyaura cross-coupling protocol for the facile synthesis of diarylmethanes. Specifically, we describe the preparation of a unique class of ligands, 2,4-diarylquinolines, and demonstrate their application in nickel-catalyzed fragment couplings between alkyltrifluoroborates and haloarenes. We detail the synthesis of the most enabling ligand, PPQN2,4-di-OMe, on a gram scale via sequential Grignard reaction and Friedländer condensation. We also outline how coupling reactions are performed without external photocatalysts under violet light irradiation.For complete details on the use and execution of this protocol, please refer to Li et al. (2022b). : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.