27853-93-6Relevant academic research and scientific papers
Ni-Catalyzed Alkenylation of Ketone Enolates under Mild Conditions: Catalyst Identification and Optimization
Grigalunas, Michael,Ankner, Tobias,Norrby, Per-Ola,Wiest, Olaf,Helquist, Paul
supporting information, p. 7019 - 7022 (2015/06/25)
A procedure for Ni-catalyzed cross-coupling of ketone enolates with alkenyl halides has been developed. Intermolecular coupling of aromatic and aliphatic ketone lithium enolates with a variety of alkenyl halides is achieved in the presence of Ni(cod)2 catalyst (5 mol %), an N-heterocyclic carbene (NHC) ligand, and LiI (10 mol %) at 6-22 °C for 0.5-12 h with yields of up to 90%. During the initial development of this reaction, a misleading result with respect to the actual active catalyst was obtained using commercially available Q-Phos ligand, which was found to contain a trace of Pd metal contaminant sufficient to catalyze the reaction. However, under the final conditions optimized for Ni(cod)2 in the presence of an NHC ligand, Pd was incompetent as a catalyst.
