Influence of catalyst nuclearity on copper-catalyzed aerobic alcohol oxidation

Abstract

Trinuclear copper(ii)–triazolyl complexes exhibited higher activities for aerobic alcohol oxidation than the related mononuclear copper(ii) catalyst, most likely due to increased Lewis acidity at copper instead of more reducible copper(ii) centers.

Unsymmetrical PEG-substituted tris(triazolyl)amines as bi-functional surfactants for copper-catalyzed aerobic oxidation of alcohols in water

“…Copper catalyst systems inspired by copper-containing oxidase enzymes have been shown to efficiently promote aerobic alcohol oxidation under mild conditions. [1][2][3][4] Semmelhack and co-workers first reported the use of O 2 as an oxidant in the catalyst system CuCl/TEMPO/DMF (TEMPO = 2,2,6,6tetramethylpiperidinyl-1-oxyl, DMF = N,N-dimethylformamide) to oxidize primary alcohols to aldehydes under atmospheric pressure. 5 Subsequently, Sheldon, 6 Koskinen, 7 and Stahl 8 incorporated 2,2 0 -bipyridine as the ligand and bases including KO t Bu, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), and NMI (N-methylimidazole) to improve copper-catalyzed alcohol oxidation under O 2 or ambient air in CH 3 CN.…”