| We have shown that 1,5-diaza-cis-decalin is a useful ligand for the copper-catalyzed oxidative biaryl coupling of 2-naphthol derivatives, providing the biaryl products in up to 93% ee. Although this reaction provides a useful synthetic method to access enantiomerically enriched 3,3'-substituted BINOLs the catalyst is not useful in providing enantiomerically enriched BINOL or bisphenolic products. Therefore, engineering a catalyst system for these transformations requires knowledge of the mechanism. Structure activity relationships, kinetics, and crystallographic data have been collected to probe the mechanism of this reaction. Analysis of the data indicates a two-phase reaction with an initial burst as well as a potentially unusual role for oxygen in the steady state. |
