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Mechanistic study of asymmetric oxidative biaryl coupling: evidence for self-processing of the copper catalyst to achieve control of oxidase vs oxygenase activity.

ABSTRACT: Copper(I) and copper(II) 1,5-diaza-cis-decalin complexes [(N2)Cu] are effective precatalysts for aerobic oxidative coupling of naphthol substrates. Mechanistic studies, however, reveal that these complexes are not the reactive form of the catalyst under steady-state conditions. Rather, the active catalyst forms in a presteady-state self-processing step that involves oxygenation of the naphthol substrate. The oxygenated substrate, NapHOX, serves as a cofactor that combines with the (N2)Cu complexes to achieve highly selective, steady-state oxidase reactivity (aerobic oxidative biaryl coupling).

SUBMITTER: Hewgley JB

PROVIDER: S-EPMC2897702 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Mechanistic study of asymmetric oxidative biaryl coupling: evidence for self-processing of the copper catalyst to achieve control of oxidase vs oxygenase activity.

Hewgley J Brian JB Stahl Shannon S SS Kozlowski Marisa C MC

Journal of the American Chemical Society 20080819 37

Copper(I) and copper(II) 1,5-diaza-cis-decalin complexes [(N2)Cu] are effective precatalysts for aerobic oxidative coupling of naphthol substrates. Mechanistic studies, however, reveal that these complexes are not the reactive form of the catalyst under steady-state conditions. Rather, the active catalyst forms in a presteady-state self-processing step that involves oxygenation of the naphthol substrate. The oxygenated substrate, NapHOX, serves as a cofactor that combines with the (N2)Cu complex ...[more]

PMID: 18710234

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