The bis(bipyridine)copper(II)-induced activation of dioxygen for the catalytic dehydrogenation of alcohols

Article abstract of DOI:10.1021/ja00061a023

The combination of bis(bipyridine)copper(II) [Cu¹¹(bpy)₂²⁺] and 2 equiv of base [HO^- or HOC(O)O^- ] with excess alcohol (e.g., PhCH₂OH) in an O₂-saturated acetonitrile solution results in the rapid, catalytic transformation of the alcohol to its aldehyde (or ketone for secondary alcohols). The rate of the process is first-order each in substrate, catalyst, and O₂ concentration with an apparent rate constant, k, for PhCH₂OH of 68 ± 9 M^-2s^-1. Aliphatic primary alcohols react 4-20 times slower, secondary alcohols react 2-10 times slower than primary alcohols, and α-allylic alcohols react 2-4 times slower than PhCH₂OH. The buildup of water (the coproduct) deactivates the catalyst via its reduction to the Cu(I) state. In the absence of alcohol, the catalyst initiates the auto-oxygenation of aldehydes to carboxylic acids.