Chemoselective H/D exchange catalyzed by nickel nanoparticles stabilized by N-heterocyclic carbene ligands. Issue 29 (17th July 2020)

• Record Type: Journal Article
• Authors: Bouzouita, Donia; Asensio, Juan M.; Pfeifer, Viktor; Palazzolo, Alberto; Lecante, Pierre; Pieters, Grégory; Feuillastre, Sophie; Tricard, Simon; Chaudret, Bruno
• Is Part Of: Nanoscale. Volume 12:Issue 29(2020)
• Page Start: 15736
• Page End: 15742
• Publication Date: 2020-07-17
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d0nr04384b
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Noble metal-free nanoparticles are used as catalysts for H/D exchange, with a regioselectivity tuned by the nature of the ligands. Abstract : With this work, we report the synthesis and full characterization of nickel nanoparticles (NPs) stabilized by N-heterocyclic carbene (NHC) ligands, namely 1, 3-bis(cyclohexyl)-1, 3-dihydro-2 H -imidazol-2-ylidene (ICy) and 1, 3-bis(2, 4, 6-trimethylphenyl)-1, 3-dihydro-2 H -imidazol-2-ylidene (IMes). Although the resulting NPs have the same size, they display different magnetic properties and different reactivities, which result from ligand effects. In the context of H/D exchange on pharmaceutically relevant heterocycles, Ni@NHC shows a high chemoselectivity, avoiding the formation of undesired reduced side-products and enabling a variety of H/D exchange on nitrogen-containing aromatic compounds. Using 2-phenylpyridine as a model substrate, it was observed that deuteration occurred preferably at the α position of the nitrogen atom, which is the most accessible position for the C–H activation. In addition, Ni@IMes NPs are also able to fully deuterate the ortho positions of the phenyl substituents.