Nickel complexes of primary amido-functionalized N-Heterocyclic carbene ligands: Synthesis, characterization, and base-free transfer hydrogenation

Publication date: Available online 18 July 2018Source: Journal of Organometallic ChemistryAuthor(s): Tiffany V. Roach, Michelle L. Schmitz, Valkyrie A. Leach, Marcus D. Miller, Benny C. Chan, Steven E. KalmanAbstractThree new nickel complexes featuring primary amido-functionalized N-heterocyclic carbene ligands have been synthesized and characterized using NMR spectroscopy, combustion analysis, and, in one case, single crystal x-ray diffraction. Each complex serves as a pre-catalyst for base-free transfer hydrogenation of aryl ketones in air using 2-propanol or 2-butanol as the solvent and hydrogen donor. Furthermore, in methanol-d4 solutions of the nickel complexes, hydrogen-deuterium exchange is observed on the ligands at moderate temperatures. These nickel complexes represent rare examples of transfer hydrogenation catalysts that operate under base-free and aerobic conditions.Graphical abstract

Source: Journal of Organometallic Chemistry - July 19, 2018 Category: Chemistry Source Type: research