Direct Access to Isotopically Labeled Aliphatic Ketones Mediated by Nickel(I) Activation

An extensive range of functionalized aliphatic ketones with good functional‐group tolerance has been prepared by a NiI‐promoted coupling of either primary or secondary alkyl iodides with NN2 pincer NiII‐acyl complexes. The latter were easily accessed from the corresponding NiII‐alkyl complexes with stoichiometric CO. This Ni‐mediated carbonylative coupling is adaptable to late‐stage carbon isotope labeling, as illustrated by the preparation of isotopically labelled pharmaceuticals. Preliminary investigations suggest the intermediacy of carbon‐centered radicals. Ideal zum Markieren: NiI‐Komplexe können die carbonylierende Kupplung von NiII‐Acyl‐Komplexen mit primären und sekundären Iodiden vermitteln; dies bietet eine allgemeine Methode zur Synthese aliphatischer Ketone direkt aus CO. Die Methode ist ideal für die Kohlenstoffisotopenmarkierung, wie anhand des Zugangs zu biologisch aktiven, 13C‐ und 14C‐haltigen Molekülen illustriert wird.