Copper(I)−α-Ketocarboxylate Complexes: Characterization and O2 Reactions That Yield Copper−Oxygen Intermediates Capable of Hydroxylating Arenes
journal contributionposted on 21.11.2007, 00:00 by Sungjun Hong, Stefan M. Huber, Laura Gagliardi, Christopher C. Cramer, William B. Tolman
A series of copper(I)−α-ketocarboxylate complexes have been prepared and shown to exhibit variable coordination modes of the α-ketocarboxylate ligand. Reaction with O2 induces decarboxylation of this ligand, and the derived copper−oxygen intermediate(s) has been intercepted, resulting in hydroxylation of an arene substituent on the supporting N-donor ligand. Theoretical calculations have provided intriguing mechanistic notions for the process, notably implicating hydroxylation pathways that involve novel [CuI−OOC(O)R] and [CuII−O-• ↔ CuIIIO2-]+ species.