Copper-catalyzed C-alkylation of secondary alcohols and methyl ketones with alcohols employing the aerobic relay race methodology.

By employing aerobic oxidation to aldehydes as a more effective alcohol activation strategy, ligand-free copper catalysts were found to be superior catalysts than other metals in aerobic dehydrative β-alkylation of secondary alcohols and α-alkylation of methyl ketones using alcohols as the green alkylating reagents. Based on our mechanistic studies and also supported by the literature, we deduce that the newly-proposed relay race process rather than the conventional borrowing hydrogen-type mechanisms should be the most possible and a more rational mechanism for the aerobic C-alkylation reactions. This journal is © The Royal Society of Chemistry 2012