Synthesis of unsymmetrical biaryls via "kinetic" higher order cyanocuprates: Scope, limitations, and spectroscopic insights

Article abstract of DOI:10.1021/ja00073a051

Treatment of lower order arylcyanocuprates ArCu(CN)Li with 1 equiv of an aryllithium (Ar′Li) at temperatures around-125°C leads to higher order reagents Ar(Ar′)Cu(CN)Li₂. Upon exposure of such reagents at this temperature to ground-state molecular oxygen, good yields of the unsymmetrical biaryl Ar-Ar′ can be realized. Several different types of aryl ligands have been examined, including naphthalenes, to assess the generality of this method. Spectroscopic data (¹³C NMR) have been obtained on three different cuprates at -130°C and at higher temperatures to determine if their kinetic nature, as illustrated by their synthetic chemistry, can be substantiated by physical means.